# Choosing the right brand for a mini-split



## sportbikerider78 (Mar 21, 2018)

Time to get AC!

What brand do you guys suggest and why?  This will be a 3 head unit with one compressor and about 42000-48000BTU...which is about 3.5 ton.

It will be a DIY for me..so any thoughts you have would be great.  

Thanks guys.

Here are a couple I have been looking at but have no data for one over the other.

https://www.ecomfort.com/Mitsubishi-M3H42W12151800-B/p57088.html


Looks like LG is about $1k more over Mitsubishi.
https://www.ecomfort.com/LG-L3L42W09151800/p78886.html


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## Tegbert (Mar 21, 2018)

I’m only seeing a 50 dollar difference between those two that you linked. The lg has a higher seer rating though but one smaller headway 9k versus the Mitsubishi at 12k. Don’t forget the line sets either if you didn’t know that they don’t come with them. And the flaring tools and vacuum pump and such to evacuate the lines. 

I’ve only known people with Mitsubishi and daikin units I haven’t met anyone with an lg but that doesn’t mean much just what the installers use around here. 

Also if you diy a lot of manufacturers will not warranty the units if something happens. 

Other than that i have nothing useful to add. I’m in the same boat right now trying to size a mini split for our home. 


Lopi Rockport
Blaze King Ashford 25


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## sportbikerider78 (Mar 22, 2018)

Ok..thanks for the info.  What I was going to do is do most of the install but have a refrigeration guy come out, test the lines and get the unit running.  I was going to do all of the mechanical connections and hang the units.  Really not that much to it, other than lots of grunt work with 3 head units going up to 50' from heat pump.

These units certainly vary greatly in price!  Significantly cheaper.  They seem to get good reviews...at least on this site.
https://www.alpinehomeair.com/viewp...w5yoGpdSORq-Lj0ExMXC4YoQriRNZZX4aAq7rEALw_wcB


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## maple1 (Mar 22, 2018)

I don't have one but hope to some day.

From the reading & researching & talking I've done - it would be a Mitsubishi, Daikin, or Fujitsu. Those seem to be the big 3 in performance & quality, and don't think there's much difference in performance or price.


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## CaptSpiff (Mar 22, 2018)

sportbikerider78 said:


> ....  I was going to do all of the mechanical connections and hang the units.  Really not that much to it, other than lots of grunt work with 3 head units going up to 50' from heat pump.



Others here with lots of experience. Mine is limited, but I recall reading that the units are all pre-charged and line length is super critical. I think 50' puts you near that limit. Not sure if the multi head unit has specific total line length.


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## sportbikerider78 (Mar 23, 2018)

Yup..I'll look into all the details before I do the install.  I have seen many units go up a wall, around a corner, into a house, and then to bedrooms on the second floor. Way over 50'. 
We will see.

Regaring "hyper heat" for the mitsubishi's...at what temperature does it make sense to have this?  Meaning, how low will the heat pump crank out heat in the cold without paying another ~$1,000 for this feature?


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## Brian26 (Mar 24, 2018)

I know these things cost a fortune to have a company install but your are essentially going to get zero warranty. Mitsubishi gives you a full 12 year warranty only when installed from one of their licensed dealers. You diy and its not charged right and it blows in a year they are going cover nothing. Thats a big gamble with a 6k Mistubshi minisplit. My neighbor had I believe that exact Mitsubishi unit you listed installed. I think he said he paid around 10 or 12k to have it installed. Twice the price but he doesn't have to worry about it for 12 years.

 I think you will also find if you call most reputable local hvac companies nobody will want to touch the refrigeration side on something you installed. You are mostly likely left to finding and hvac guy to do it on the side like on the weekend or something. Any if something goes wrong hes going to want nothing to do with it. 

 I can see attempting a DIY on cheap $1000 minisplit and if it last a year or two and blows its not a big loss. In no way would I spend 6k on a Mitsubishi and attempt to diy with no warranty. Notice on that website you linked there is nothing listed about the warranty.


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## sportbikerider78 (Mar 24, 2018)

I'm willing to take that gamble.  Hell, even if it blew up right away and I had to order another compressor unit I'd still make out ahead on an installation cost over 5k.

This isn't voodoo rocket science.  We are talking about leak testing. Pulling a vacuum, then charging the unit.  Companies charge a fortune, but that company is just made up of a bunch of medium paid guys that usually, like some extra cash jobs on the side.  

I'm looking forward to learning to flare a copper tube, getting the right tools and then having someone come take care of the rest of it.  Not worried at all.

I just research the heck out of projects to hedge my bets.  I've always worked


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## fbelec (Mar 26, 2018)

just make sure you follow the directions with the unit. to a tee. i can't remember what brand it was but on of the brands used a different size line set. if you can see if you can find out when the company you choose has a class. just get a certificate on the unit and i think you are ok. classes are i think just one day. if i can nail the hvac guy i work with to use one brand i can get my cert. even tho i'm a electrician. he's up in the air because all are compressors are made in china.


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## peakbagger (Mar 26, 2018)

The techs I talked to several years ago claimed that at best I might get heat down to 40 degrees without it. I have never looked the details, but the hyper heat option has several pieces but the big one seems to be a variable speed compressor.

FYI, the multihead Mitsubishis used to have a bad rep with the same techs. They claimed that unlike the single head units, the multiheads required far more servicing. This was early on when the hyper heat multi head were just coming out, so it have been growing pains.


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## fbelec (Mar 27, 2018)

a mini split heat pump is different from the standard ducted heat pump temp wise the last ducted heat pump i wired was a york affinity. it would work down to 32 to 36 degrees. it was field set then at that point it would switch to the 97 or 98% eff. nat gas burner that was modulating. the standard mini split heat pump will heat down to 0 degrees and then there are sum that go down to -15. i wired a few reg heat mini's i can remember one i did over a garage that when i tried it out when wired it was throwing really good heat at a 17 degree outdoor temp


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## maple1 (Mar 27, 2018)

sportbikerider78 said:


> Regaring "hyper heat" for the mitsubishi's...at what temperature does it make sense to have this?  Meaning, how low will the heat pump crank out heat in the cold without paying another ~$1,000 for this feature?



I'm not sure about the exact answer there - but to me it would be missed opportunity to not go with it even if it is $1000 more. In climates anywhere near moderate, I don't think there is a more efficient way to heat.  Even if it won't do 100% of your heat.


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## vinny11950 (Mar 27, 2018)

sportbikerider78 said:


> Time to get AC!
> 
> What brand do you guys suggest and why?  This will be a 3 head unit with one compressor and about 42000-48000BTU...which is about 3.5 ton.
> 
> ...



Good thread.  I too have been thinking of getting another heating system in the house to back up the pellet stove and the electric baseboard heaters which are never used.

I have been trying to figure out how much electricity the unit would use to estimate cost per month.  I found this video online



Of course Long Island electricity charges are double everywhere else in NY state, but it may still be worth it.

If you read the comments below the video, viewers explain the ghost load issue of the unit as the heater for the unit itself (important process).

I wonder if a heat pump would be considered a main source of heating.


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## peakbagger (Mar 27, 2018)

I run my Mitsubishi Hyper Heat all winter whenever the outdoor temps are over 20 F. It will put out heat down to -12 F but far less of it and COP drops to the point where I am better off using a space heater. I have surplus PV generation that is net metered so its normally "free" to run although I must admit that cold stretch in late January into February chewed up my surplus. I may actually have an electric bill this month after 5 years of not having one. Once it gets over 30 F at night the boiler definitely gets shut down. The thing to realize with a mini split for heating is set it and forget it, dont let the house get cold and then expect it going to heat it right back up quickly. It takes a long time for it to catch up as its 12000 btus an hour compared to a 100,000 BTU oil boiler and a 100,000 BTU wood boiler.


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## sportbikerider78 (Apr 23, 2018)

I'm going to use this unit primarily for cooling.  I have a wood stove and a new oil boiler system.  Not too worried about heat. A $1000 buys a lot of oil!  

I spoke to a Mitsubishi distributor and we will be working the details out.


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## begreen (Apr 26, 2018)

Spoke with a local dealer last weekend at an Earth Day event about the state of art in these systems. He is sold on Mitsubishi for developing solutions for the American market. They have a new 5 ton unit that produces 60K btus at 17ºF.


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## maple1 (Apr 27, 2018)

sportbikerider78 said:


> I'm going to use this unit primarily for cooling.  I have a wood stove and a new oil boiler system.  Not too worried about heat. A $1000 buys a lot of oil!
> 
> I spoke to a Mitsubishi distributor and we will be working the details out.



True but that $1000 up front cost can also displace a lot of oil with lower cost heat over its lifetime. I think with our house that much oil would only be maybe 2 months  of heat at best.


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## sportbikerider78 (Apr 28, 2018)

I do a 5 year ROI on home purchases.  If they don't pay back in 5 years, they aren't worth it to me.  I don't know if I will be living here in 10 years.

I would use it in shoulder season because that is when a heat pump is most effective.  I can still do that without the HyperHeat feature.  To me there is no payback with a great woodstove and new furnace.


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## begreen (Apr 28, 2018)

Part of the ROI can come into play on resale too if the investment is one that has value for the future buyer.


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## sportbikerider78 (May 18, 2018)

Thanks for the help and advice guys.  I am going with the ~2.5T/30,000BTU unit with 3 heads from Mitsubishi.


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## Soundchasm (May 20, 2018)

Good luck on the endeavor.  We installed a 1-ton Mitsubishi mini-split in a well-insulated sun room.  A general contractor installed it during a remodel.  It's pretty neat.  It got its own dedicated 220V line and breaker.

It did need service for a leak.  My mind has blanked out the painful parts, but a few connections were redone.  We stop using the room when it gets to 30-40 degrees.  Even though the walls, windows and ceiling are excellent, my big, giant alien brain didn't notice that the "floor" is the roof of the poured concrete garage!  IR gun reads the floor at 40 degrees in the winter.

Make sure you run it for 15-20 minutes once a month in the winter as maintenance.

I thought the max line set was about two stories.  Shorter is better.

The last caution is that the refrigerants work at stupid high pressures.  Even a tiny, tiny little crack in a copper flare joint and you're doomed.  Whoever does that has to be an expert.  And the line ought to be surgically clean inside.

All those cautions aside, it's still kind of neat to watch the thing work.  And I don't really see it on my electric bill, which I watch like a hawk.

We went through a MAJOR replacement of the 3-ton for the house.  All the research I did indicated that you're not picking equipment - you're picking the installer!!  So I found a wonderfully OCD guy with decades of experience and so far so good.

Last thought, but you've probably already gone there.  Would three separate units be possible?  If anything happened you wouldn't have all your eggs in one basket.


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## begreen (May 20, 2018)

Have you considered laying down some insulation under flooring in the cold room? It can make a huge difference. My small shop is on slab and I couldn't heat it very well with an electric heater. The heater would run continuously and it still always felt cold even after hours of running. I put down some foam interlocking flooring in there and the difference is amazing. Now I can easily warm up the place in an hour now. There are more elegant solutions for a nice finished room, but they make this stuff in colors instead of the industrial grey that I used in the shop if you want an inexpensive solution.


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## sportbikerider78 (May 20, 2018)

Thanks for the input.  I don't think these units are different pressures than other home AC heat pumps, are they?  

No way I can do 3 units.  That would involve more breakers.  3 outdoor line sets.  3 disconnects.  3 heat pumps.  That would take my heat pump costs from $2700 to over $4000 and greatly increase installation costs.


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## begreen (May 20, 2018)

I have a couple friends that have multi-head mini-splits. They have been fine. The only issue has been with one that had a control circuit board burn out due to a power surge. This was a Fujitsu system. The other has a Mitsubishi system and it's been trouble free. Both were installed about 5 years ago. Locally due to our rural power, the installer now recommends adding surge protection for the hp circuit to protect the electronics.


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## Soundchasm (May 20, 2018)

sportbikerider78 said:


> Thanks for the input.  I don't think these units are different pressures than other home AC heat pumps, are they?
> 
> No way I can do 3 units.  That would involve more breakers.  3 outdoor line sets.  3 disconnects.  3 heat pumps.  That would take my heat pump costs from $2700 to over $4000 and greatly increase installation costs.



I can't quote anything chapter and verse because I've slept since then, but methinks that ye old Freon was a very low pressure and connections weren't critical.  The newer refrigerants are much higher pressures and a last ditch kind of repair like soldering a connection has to be upgraded to brazing, or something like that.

I hope I'm not spreading misinformation, but my overall impression is that the connections are critical and the lines need to be clean.

Our 1-ton unit was under a grand for the air handler, line set and compressor.  I think that was everything.  But you are right about breakers and disconnects.  Just to flog the idea and give options, you could stagger installations of individual units every six months or so.

But best to stick to what you've researched and just solve the problem.


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## Soundchasm (May 20, 2018)

begreen said:


> Have you considered laying down some insulation under flooring in the cold room? It can make a huge difference. My small shop is on slab and I couldn't heat it very well with an electric heater. The heater would run continuously and it still always felt cold even after hours of running. I put down some foam interlocking flooring in there and the difference is amazing. Now I can easily warm up the place in an hour now. There are more elegant solutions for a nice finished room, but they make this stuff in colors instead of the industrial grey that I used in the shop if you want an inexpensive solution.



The wife would like to use the room more, and we're kicking around ideas.  It's a tile floor.  She mentioned a rug, but the room is the main traffic route for the dogs going in and out, and from time to time they're not in exactly pristine condition!  ;-)


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## peakbagger (May 20, 2018)

When I had my mini split charged by a tech I had run the copper lines but left them loose at each end. They were preflared but the tech cut off the flares and did a new set as he had had bad luck with factory preflares. The other thing he did was purged the lines with inert gas (I think it was an argon blend). He then pulled a vacuum and let the gauge set for about 15 minutes. He then charged the unit and pulled the required vacuum and let it set for about 15 minutes. I have read that its best to leave them overnight and see if there is any loss but expect few techs would. 

I have regular AC only minisplit that I want to switch to a cold climate unit. The lines are foamed into my ceiling and would be bear to change. The tech I have talked to are very hesitant to reuse the existing lines even though its the same brand and gas type.

Manufacturers are starting to switch to CO2 reportedly they require even higher pressures


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## sportbikerider78 (May 31, 2018)

My 42kBTU unit is on its way.  Shipped yesterday. 

I will have 15k head, 15k head and a 12k head unit.

I have a friend that is an electrician and he will be coming to home depot with me to buy everything I need to install 2 20A fuses, run the cable inside, run outside to my disconnect, wire the disconnect and then to the unit. 

Good times.  90F at my house yesterday but this next week or so is a nice temp to get things done.


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## jeanw (Jun 1, 2018)

we happy with a bigger Samsung  and a smaller Friedrich. course not used much since unfortunately not been here much cause of family problems. But its on now in LR. house is only under 1500 sq ft.
  now if just could get a replacement remote for Samsung. No one will help. no eaters around. BIL and brother (in the trades) helped back in the the early years 2000's
  just a saying


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## sportbikerider78 (Jun 1, 2018)

Interesting totally unexpected crossroads...
Boss called me last night and asked it I wanted to move back towards my hometown.  

Now..do I install the mini split to increase home value or bring it with me to use on a new home that I will build?  
I'm leaning toward install it for home value and ease of sale.


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## begreen (Jun 4, 2018)

Congratulations. Hope the boss makes it worth your while. If so you will have to weigh the options like how soon you would move, hvac options in the new home, etc.


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## peakbagger (Jun 4, 2018)

IMHO I would take it with you unless your local housing market is tight or the lack of AC is big impact to new buyers. I don't think you will get anywhere near what you spent to buy and install out of the house price. Folks rarely pay extra for mechanical systems, they will discount if stuff doesn't work to get deal but rarely will they pay for recent upgrades.


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## sportbikerider78 (Jun 4, 2018)

Thanks for the feedback.  What I was thinking is that it would make me more competitive with nicer homes in the area.  I have one of the cheapest homes on the block ($260-300k vs $500k+) and i would.like to get as much as possible.
AC isn't an absolute must in this area, but it certainly is a nice to have.  Last summer had many many wks in the 90's.
I'm thinking that your average person that drops  $300k on a home is going to want it.


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## sportbikerider78 (Jun 11, 2018)

Picked up the units today.  Doing the wiring with a friend in the next week. 
Exciting this project is finally kicking off.


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## sportbikerider78 (Jun 13, 2018)

Doing some parts shopping tonight. 

Amazon has by FAR the cheapest pricing on line sets. 
1/4" x 3/8" x 50' insulated $99 shipped.

Unfortunately, I can't order a continuous 100'-120' set and cut my own.  Oh well.  This is still the way to go.


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## sportbikerider78 (Jun 13, 2018)

Pics or it didn't happen, right?


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## sportbikerider78 (Jun 18, 2018)

All the wall units hung on Saturday.

Instead of buying a kit (for $15 each) to go between inside wall and outside wall.  I bought a section of 3" pvc pipe and used a 3.5" hole saw.  Fit was perfect.  Because I was using a bigger than recommned hole, I needed to move the hole center up a big more then the template showed.

The template Mits. provides on the back of the bracket is downright awesome.  Tons of holes.  Perfect place to lock your tape measure into and measure the exact spot to 5 1/8" hole center.  I could not have been happier with it.


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## sportbikerider78 (Jun 18, 2018)

Outside view


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## sportbikerider78 (Jun 18, 2018)

Complete


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## sportbikerider78 (Jun 25, 2018)

Some progress this weekend.  Pad is poured about 4-6". Graded to drain, since we do have a lot of rain in our area.  Main thing for me was to allow it to drain and float.  Of course, just as I was finishing the pour it rained (t-storm) and I forgot to cover it, since it was a mad dash to get my tools out of the rain.  The top is a touch sandy and flaky, which is characteristic of too much water.  Whatever. Not a big deal.  Most guys use patio blocks and this is exponentially better.

The condenser footprint is 40x15 and I poured a 48x22.5.

The picture makes it look out of square on the left side, but it isn't.  The wavyness towards the foundation is kids hand prints.  





My electrician friend went to HD with me to get supplies.  Wow. 8/3 wire is pricey.  $187 for 50'.  Got a disconnect for $15.  40A breaker for $10-20 and some misc other supplies.
Remaining lineset and channels to conceal the linesets against the siding coming in today.

Have a heating and cooling professional over in a few days to quote connecting linesets, pulling a vac, charging the system.  If he will install the linesets for a little more money, I'll have him do that too.


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## peakbagger (Jun 25, 2018)

Are you putting the outdoor unit at ground level?. Generally they get put up elevated off the ground in snow zones well above the typical snow pack height to keep the unit from getting filled up with snow.


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## sportbikerider78 (Jun 25, 2018)

peakbagger said:


> Are you putting the outdoor unit at ground level?. Generally they get put up elevated off the ground in snow zones well above the typical snow pack height to keep the unit from getting filled up with snow.



That is true.  This will not be a source of heat in the winter and (you can't see it in the pic) but it is under my deck by about 4-5'.  That is why I placed it under there...to keep it free of snowfall.  Getting it packed with snow is a valid concern when it is being used for heat.  
After the install is complete, I'll also create a small roof for it under my deck to keep rain from dripping between boards onto it.


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## Soundchasm (Jun 25, 2018)

If you can't have a little fun with concrete, what's the point??  ;-)

You've probably already thought of it, but do you have access to hose off the radiator, or fins, or whatever you call it?  Here, deep in cottonwood territory, I have to do mine at least twice a year.


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## sportbikerider78 (Jun 25, 2018)

Soundchasm said:


> If you can't have a little fun with concrete, what's the point??  ;-)
> 
> You've probably already thought of it, but do you have access to hose off the radiator, or fins, or whatever you call it?  Here, deep in cottonwood territory, I have to do mine at least twice a year.


Yep...about 10 feet away.  
Good call.


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## fbelec (Jun 26, 2018)

how many tons is your unit?


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## sportbikerider78 (Jun 26, 2018)

fbelec said:


> how many tons is your unit?


3.5


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## fbelec (Jun 26, 2018)

i ask because there is a minimum amp circuit and a maximum amp circuit rating on the units. if it goes bad and burns up the company can refuse the warranty if to big a breaker is on it. i think it may be 30 for that. with those inverter compressors there is no surge current like a regular compressor so there is no need to worry about the circuit start up current


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## sportbikerider78 (Jun 27, 2018)

fbelec said:


> i ask because there is a minimum amp circuit and a maximum amp circuit rating on the units. if it goes bad and burns up the company can refuse the warranty if to big a breaker is on it. i think it may be 30 for that. with those inverter compressors there is no surge current like a regular compressor so there is no need to worry about the circuit start up current



The min rating is 31.9A max is 40A.  There is no 31.9A breaker that I know of.

Our plan is to run 8/3wire on a 40A breaker.


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## Ashful (Jun 27, 2018)

sportbikerider78 said:


> The min rating is 31.9A max is 40A.  There is no 31.9A breaker that I know of.
> 
> Our plan is to run 8/3wire on a 40A breaker.



Check with a real electrician on this, but I believe there’s a requirement that all dedicated breakers must be sized at rated load divided by 0.8, such that rated load is never more than 80% of breaker capacity on a dedicated line.  This would dictate a 50A breaker, if we used the max load number, but I’m wondering if they’ve already done that math for you here.  In other words, rated load = 32A/0.8 => 40A breaker.


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## sportbikerider78 (Jun 27, 2018)

Ashful said:


> Check with a real electrician on this, but I believe there’s a requirement that all dedicated breakers must be sized at rated load divided by 0.8, such that rated load is never more than 80% of breaker capacity on a dedicated line.  This would dictate a 50A breaker, if we used the max load number, but I’m wondering if they’ve already done that math for you here.  In other words, rated load = 32A/0.8 => 40A breaker.


My friend is an electrician that is helping with the wiring.

Here is all the info the installation manual provides.  You can see it says "Max Fuse Size 40A".




Everything I have read and seen on line about this unit is that it doesn't even pull the minimum 31A at start up.  These do not have a motor start massive amperage draw because they don't have a 'stupid' AC motor...they have an inverter driven AC motor which is being driving by a programmed startup profile.
The unit will be running around 15-20A most of the time.  Again,,from what I have see from videos online.
BTW,,,Mitsubishi makes some of the best inverters/Variable Frequency Drives (VFD's) on the market.  As a sales engineer, they are a great product to represent.  The only bad part (for the salesman) is that once you sell them, you never sell the same one again!


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## Ashful (Jun 27, 2018)

That clears it up.  They say right there, 31.9 amps rating, max fuse size 40 amps.  You’re already on the right track, excuse my tangent.


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## sportbikerider78 (Jun 27, 2018)

Ashful said:


> That clears it up.  They say right there, 31.9 amps rating, max fuse size 40 amps.  You’re already on the right track, excuse my tangent.


No sweat.  I appreciate the interest.  

This manual has been my reading material for the past couple of weeks.  It kinda sucks.  I wish they would have an American technician/electrician add some comments to better represent standards here.  

In this market, the US is likely very under-represented for sales.  I can see why it is not worth the time.


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## sportbikerider78 (Jun 27, 2018)

Installed 3 of these kits from Amazon last night.
https://www.amazon.com/gp/product/B00CWNQL4C/?tag=hearthamazon-20

It all went pretty smooth.  Will use the flexible section to cover through the deck, since there a 3/4" step out away from the house where the metal flashing is directly below the siding.  I could not go straight down.  It was VERY easy to cut with a vibratory tool.  Perfect tool for the job.  I used coated deck screws to secure it to the siding and pre-drilled all the holes to prevent the siding from pulling outwards.  Worked great.
No worries about water, since this is all below a nice 2-3' eve in the roof.

It looks crooked in the pic,,but it isn't.  Must have been the angle I took the picture.


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## Soundchasm (Jun 27, 2018)

On a comedic note, primarily to tattle on myself, I've been waiting to spray off the condensers for both the mini-split and main heat pump.  I've been keeping an eye on them all spring.  Yesterday was finally the day opportunity met ambition.

The main 3 ton heat pump wasn't bad - pretty much just what I expected.  HOWEVER, the mini-split condenser looked like a dryer filter!!  Crap!!  Of course it comes right off, but that had to happen in about a month, I think.

The units are 50' apart.  Main heat pump at ground level; mini-split at second floor.  For something I've trained myself to glance at all the time, I either forgot to glance or that happened overnight.  ;-)  Maybe it was a little of both.

I'd post a photo but it's too embarrassing!


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## sportbikerider78 (Jun 27, 2018)

When I bought my townhome in CT years ago, I cleaned the condenser outside.  About an inch of s*** came off it like a rug.  I don't know if it had ever been cleaned.


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## peakbagger (Jun 27, 2018)

Looking good but expect you are going to regret not having it on line during the upcoming heat wave


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## Ashful (Jun 27, 2018)

sportbikerider78 said:


> When I bought my townhome in CT years ago, I cleaned the condenser outside.  About an inch of s*** came off it like a rug.  I don't know if it had ever been cleaned.


I have four, ranging from 3 to 24 years old.  None have ever been cleaned, nor to they look like there'd be anything to clean from them, so this is a surprise to me.  Other than a little dirt in the bottom few inches of a 48 inch tall heat exchanger, mine don't seem to pick up any visible dirt.

But, you have me curious to give it a try.  I assume you're removing the top grill, and spraying from inside toward outside, with a garden hose?


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## sportbikerider78 (Jun 28, 2018)

peakbagger said:


> Looking good but expect you are going to regret not having it on line during the upcoming heat wave


Yeah.  No doubt.  I was at the mercy of many others when planning this project.  Frankly, I don't think an installer could have gotten it done any quicker, being how my units arrived at the start of peak AC season.  I was waiting for about 1 month to iron out the discounting that i would get with Mitsubishi.  All said an done...I have a big smile on my face.


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## sportbikerider78 (Jun 28, 2018)

Ashful said:


> I have four, ranging from 3 to 24 years old.  None have ever been cleaned, nor to they look like there'd be anything to clean from them, so this is a surprise to me.  Other than a little dirt in the bottom few inches of a 48 inch tall heat exchanger, mine don't seem to pick up any visible dirt.
> 
> But, you have me curious to give it a try.  I assume you're removing the top grill, and spraying from inside toward outside, with a garden hose?


However you have to access the front of the unit where the air first hits the heat exchanger.  That is where you have to clean.


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## Ashful (Jun 28, 2018)

sportbikerider78 said:


> However you have to access the front of the unit where the air first hits the heat exchanger.  That is where you have to clean.



Yeah, but you want to blow in reverse of the airflow direction, right?  On a mini split this might be easier, I have two of those.  But on the traditional cylindrical units, it means going down in from the top.  One of mine is large enough to require a ladder to do that, but it is do-able.


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## fbelec (Jun 29, 2018)

sorry i forgot you had a electrician there. prob will draw a lot less the the rating says. i had a amprobe on a reg central air unit today it was a 3 ton and only pulling 14.9 amps. so you'll do better.


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## sportbikerider78 (Jun 29, 2018)

Power to the condenser is complete with 50A disconnect.  It was cheaper then a 40A disconnect.

Unit is anchored with concrete anchors. 

Next step is linesets and control/head unit power with 14/3 cable + the condensate line..which is easy.

The head units are two 120V hot, 1 ground and 1 low voltage communication wire. 

There is a lot of confusion on what type of cable to use to power the head units.  Many use shielded, 14/4 stranded, and a few others.  The manual only specifies 14 guage.  I called Mitsubishi technical support and the tech emphatically said "You will have no problems using 14/3 standard home romex..that is what you should use."  Music to my ears as it will be quite cheaper.  I asked about burial outdoor cable and he said that you can use that but it would be an overkill.  I couldn't find any, so standard Romex it is.


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## Ashful (Jun 29, 2018)

sportbikerider78 said:


> Power to the condenser is complete with 50A disconnect.  It was cheaper then a 40A disconnect.
> 
> Unit is anchored with concrete anchors.
> 
> ...



I have had four Mitsubishi mini split systems, three are at my current house, installed by three different installers at three different times.  Two of them made special mention of the condensate line.  Namely, it should be very highly sloped, as they have had a lot of problems with condensate lines backing up on these.


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## sportbikerider78 (Jun 29, 2018)

Ashful said:


> I have had four Mitsubishi mini split systems, three are at my current house, and all indoor units were wired with Romex.  They were installed by three different installers at three different times, so seeing they all used the same makes me think that’s the standard way of doing them.
> 
> Two of them made special mention of the condensate line.  Namely, it should be very highly sloped, as they have had a lot of problems with condensate lines backing up on these.


That's great to know..thank you for the input.  Most of the posts I saw about romex involved an old electrician throwing a fit for using romex outside.

Yup..I have at least a 15° pitch from inside to outside with my condensate tube.  Thanks for the heads up.


----------



## Ashful (Jun 29, 2018)

sportbikerider78 said:


> That's great to know..thank you for the input.  Most of the posts I saw about romex involved an old electrician throwing a fit for using romex outside.
> 
> Yup..I have at least a 15° pitch from inside to outside with my condensate tube.  Thanks for the heads up.


You know, I hate to admit this, but I was wrong.  I know they ran Romex to the indoor units at my old house, but there was a junction box between.  I just got home and checked each of the outdoor units on my current house, and they are all multiconductor THHN/THWN with black UV-rated jacket.  Sorry for posting bad info above, I will go edit that out.


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## fbelec (Jun 30, 2018)

my last code update class had a guy come in and said that the only wire legal to use is a special uf cable that is stranded wire. as of late i have changed the cable that is run in the slim duct or liquid tight for different brands between the units that are 120 or 240 volt indoor unit's to uf. anything that goes outside has to be uf cable even in pipes. uf or thhn. it's funny the last unit don't remember if it was a mitsu or daikin it had to be run from compressor to the indoor unit a 6 wire that was shielded. they wanted the shield because the didn't want interference in the units talking to the compressor. low voltage motor


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## Ashful (Jun 30, 2018)

fbelec said:


> my last code update class had a guy come in and said that the only wire legal to use is a special uf cable that is stranded wire.


Do you mean UV-resistant cable, fbelec?  There is a UV-resistant Romex variant, usually colored gray or silver.

Each of mine have flex conduit for the 240V main, and the above mentioned THWN for the run to the head unit.


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## sportbikerider78 (Jul 1, 2018)

fbelec said:


> my last code update class had a guy come in and said that the only wire legal to use is a special uf cable that is stranded wire. as of late i have changed the cable that is run in the slim duct or liquid tight for different brands between the units that are 120 or 240 volt indoor unit's to uf. anything that goes outside has to be uf cable even in pipes. uf or thhn. it's funny the last unit don't remember if it was a mitsu or daikin it had to be run from compressor to the indoor unit a 6 wire that was shielded. they wanted the shield because the didn't want interference in the units talking to the compressor. low voltage motor



That is awfully strange about the shielding needed for interference.  In the automation world, low voltage (12-24) is run very close to high voltage.  Most of the time, most is unshielded.  

If there was a large interference issue between unit communication, they wouldn't put the terminal blocks right next to each other.  

Quite frankly..no one will know what wire I used.  It will be safe.  It will be per manufacturer's recommendation.  I can sleep well.


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## begreen (Jul 1, 2018)

Depends on the application and the type of communications but EMI is real.
http://www.smar.com/en/technical-article/tips-on-shielding-and-grounding-in-industrial-automation
That said, if the manufacturer doesn't specify shielded wiring for communications, then it's likely the low voltage wiring is just for LV transformer feed, relay triggering, etc..


----------



## Ashful (Jul 1, 2018)

sportbikerider78 said:


> That is awfully strange about the shielding needed for interference.  In the automation world, low voltage (12-24) is run very close to high voltage.  Most of the time, most is unshielded.
> 
> If there was a large interference issue between unit communication, they wouldn't put the terminal blocks right next to each other.
> 
> Quite frankly..no one will know what wire I used.  It will be safe.  It will be per manufacturer's recommendation.  I can sleep well.



EMI is a huge problem in automotive, one of the number 1 technical problems that plagued auto manufacturers for 40-50 years.  With the advent of coil packs and the death of AM radio, which operated in the band of your ignition system, you just don’t hear as much about it today.  Likewise with resistive plugs and high-impedance ignition wires on small engines, the lack of which used to cause neighbors all sorts of grief, before you were born.


----------



## fbelec (Jul 2, 2018)

as far as just uv the thermostat wire we run from a c compressors is sun light resistant. the wire i'm talking about looks just like regular 14/3 uf cable the only thing that is different with the wire is stranded and not solid and as of my last code update class it was the only legal cable to use and it was made for just this application for the units that require it. i'm not sure how many are still running 120 volts between the compressor and the indoor units. we had the man that owns the wire company come and speak at the class. he is the only company that makes it. personally i run the regular uf cable and have never been called on it by the inspector but i'll bet most don't know about it. if the unit has a spec for a wire with shielding i have to put it in incase the company rep comes to the site for the unit running weird that should be in place. the shield is for the different frequency's for the communication. and yes the company reps have been out for problems which ended up being new control boards. the last board that went was on a sanyo machine. the board blew because of a not a direct hit but a near by lightning strike. cooling company's cost for that board was $750.00


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## sportbikerider78 (Jul 2, 2018)

UV is not a concern to me.  No wires will be exposed.


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## fbelec (Jul 3, 2018)

hey now is the perfect weather to see how you did


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## Soundchasm (Jul 6, 2018)

Here's a related/unrelated head's up.  Went to clean the filters on my Panasonic mini-split with a fresh, curious eye, so to speak.  I'm talking about the indoor part.  This unit is from 2010.

Holy crap, there seems to be an entire ecosystem come to life on the scroll fan and drain tray.  I'm calling a professional to get both of them out of there and clean it.  Sheesh!  Frightening.

It's clearly my responsibility to dig into this stuff and learn all about it, but it's a tough assignment to figure out what you don't know.


----------



## begreen (Jul 6, 2018)

Soundchasm said:


> Here's a related/unrelated head's up.  Went to clean the filters on my Panasonic mini-split with a fresh, curious eye, so to speak.  I'm talking about the indoor part.  This unit is from 2010.
> 
> Holy crap, there seems to be an entire ecosystem come to life on the scroll fan and drain tray.  I'm calling a professional to get both of them out of there and clean it.  Sheesh!  Frightening.
> 
> It's clearly my responsibility to dig into this stuff and learn all about it, but it's a tough assignment to figure out what you don't know.


Ordered some cleaner yesterday. Looks like I will be tackling our system's cleaning soon.


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## sportbikerider78 (Jul 8, 2018)

It will be quite expensive if you want to disconnect the head units and remove them.


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## Soundchasm (Jul 8, 2018)

sportbikerider78 said:


> It will be quite expensive if you want to disconnect the head units and remove them.



I read somewhere that somebody charged $300 for the service that I'm requesting.  Pretty vague, right?  ;-)

This guy is the installer who did my main system last December.  You really don't meet many people like him.  I've checked Youtube and there is a way to take off just enough stuff to get the scroll fan out.  But all the films are Mitsubishi and not Panasonic.

I have enough respect for this guy that if he says tear it all out and start over I won't bat an eye.


----------



## begreen (Jul 8, 2018)

Soundchasm said:


> I read somewhere that somebody charged $300 for the service that I'm requesting.  Pretty vague, right?  ;-)
> 
> This guy is the installer who did my main system last December.  You really don't meet many people like him.  I've checked Youtube and there is a way to take off just enough stuff to get the scroll fan out.  But all the films are Mitsubishi and not Panasonic.
> 
> I have enough respect for this guy that if he says tear it all out and start over I won't bat an eye.


Sounds like a good man. We are fortunate to have a similar family operation here. His business is small and wants to keep it that was so that he has a life too. His son now assists with the larger installs. I got him started on installing mini-splits around 2006 and he's done a lot of them since. Never charges a dime when he comes out to check our system in spite of me asking him for the bill.


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## Soundchasm (Jul 9, 2018)

begreen said:


> Sounds like a good man. We are fortunate to have a similar family operation here. His business is small and wants to keep it that was so that he has a life too. His son now assists with the larger installs. I got him started on installing mini-splits around 2006 and he's done a lot of them since. Never charges a dime when he comes out to check our system in spite of me asking him for the bill.



This guy has no website or even a business card and he's booked solid.  When I hired him to do our main heat pump/air handler I asked what he needed for a deposit and he told me he doesn't want a dime until I'm satisfied with the job.  When I asked about buying a labor warranty he said "I don't want your money - I don't know how long I'll be doing this".

I work with a drummer who works for him in the daytime.  He was always complaining about how Bill made them get stuff perfect that was going to be behind drywall or under a floor.  I'm sure there are young guys doing the same thing, but it's nice to meet somebody who's been doing it that way for a long time.  ;-)  They've seen it all.


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## Soundchasm (Jul 11, 2018)

OK, let me post my shame.  Ashful, there might be a way to remove the sides of your outside unit.  Turns out there was with mine.  These pics depict my best effort with the sides still on.  I got quite a good bath with the sides on.





I assure you, they're clean now...  You can see the screw hole.  Take the screw out, lift up and remove the louvers. 

Now here's the damned mini-split.  I took out a wire grid that (I guess) would stop you from jamming a broomstick up there...  Lawyers?  Bent as needed to get it out and discarded.  Couldn't figure out how to disassemble.  Gave everything a mild bleach bath so I wouldn't catch Legionnaire's Disease.  Cleaned the radiator bit with cleaner and it changed color.   Got a spray bottle, safety glasses, and shot water on the running fan until no more crap came out.  Then I used the spray bottle for one more mild bleach bath and reassembled.

If you need one, my advice is to buy two and practice disassembling the second unit....  What a PITA.







Finally, my installer mentioned a piece of advice.  2K BTUs per person as a sizing guide.  I think he's right.  My unit is definitely under-sized at only one-ton.


----------



## Ashful (Jul 11, 2018)

Thanks for posting that, Soundchasm!  I’m going to have to pull apart my minisplit heads, and see how they look.  One is in a music studio that is kept conditioned 24/7/365, due to acoustic instruments stored in there, but only actually used a few evenings per month.  Since the room stays so clean, I suspect it’s clean.  Then the other two are in my work shop, which is quite dusty with sawdust and such, so I have the pre-filters on those units.

My traditional outdoor units look like yours with the louvered covers removed, just fins covered with a cage.  I blow them off with the handheld leaf blower after each mowing (at least once per week), so they stay much cleaner than yours.  Never any grass or anything on them, like I see in that photo you posted.  I assumed you guys meant a little invisible dust between the fins on the condenser coil, which is still possible on mine, but there is no visible dirt.

On sizing, I think my traditional units are both 5 - 6 tons each, and my mini splits are 1 ton for the studio and 3 ton for the shop.  I’d have to check the name plates on the traditional units to confirm that, one is physically much bigger (but older) than the other.


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## georgepds (Jul 11, 2018)

"EMI is a huge problem in automotive, one of the number 1 technical problems that plagued auto manufacturers for 40-50 years. With the advent of coil packs and the death of AM radio, which operated in the band of your ignition system, you just don’t hear as much about it today. "

If my hearing aid is in telecoil mode ( used in theaters) it buzzes like crazy when I start my volt


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## begreen (Jul 11, 2018)

georgepds said:


> If my hearing aid is in telecoil mode ( used in theaters) it buzzes like crazy when I start my volt



LOL I'll have to try that. Didn't know about the telecoil mode being for theaters. A lot of times when I go to the cineplex theater the volume is so loud that the last thing I need is a hearing aid. Our local theater is much better.


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## Soundchasm (Jul 12, 2018)

Ashful said:


> Thanks for posting that, Soundchasm!  I’m going to have to pull apart my minisplit heads, and see how they look.  One is in a music studio that is kept conditioned 24/7/365, due to acoustic instruments stored in there, but only actually used a few evenings per month.  Since the room stays so clean, I suspect it’s clean.  Then the other two are in my work shop, which is quite dusty with sawdust and such, so I have the pre-filters on those units.
> 
> My traditional outdoor units look like yours with the louvered covers removed, just fins covered with a cage.  I blow them off with the handheld leaf blower after each mowing (at least once per week), so they stay much cleaner than yours.  Never any grass or anything on them, like I see in that photo you posted.  I assumed you guys meant a little invisible dust between the fins on the condenser coil, which is still possible on mine, but there is no visible dirt.
> 
> On sizing, I think my traditional units are both 5 - 6 tons each, and my mini splits are 1 ton for the studio and 3 ton for the shop.  I’d have to check the name plates on the traditional units to confirm that, one is physically much bigger (but older) than the other.



Ashful, our sunroom isn't what I'd call a dusty environment at all.  That's 7-8 years of me not knowing that fan was there.

My installer gave me a spray bottle of Ace Evap-Klean Plus.  16 OZ would be sufficient for one mini-split.  It did change the color from a light tan back to raw metal.  Impressive, actually.

I'm surrounded by Cottonwood and Sycamores and Dandelions.  What you see on my main unit is December 2017 to present.  Not exactly chronic neglect...

My mind is blown at the thought of a perpetually clean outside unit!!  ;-)

You need to make a separate post as to what is in your music room, and I need to know a detailed explanation as to why it's used ONLY a few evenings per month!


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## fbelec (Jul 12, 2018)

soundchasm you must have been feeling sick when they were running. nice job. a short funny story i had my car air cond on and would get a little mold smell followed by a stuffed nose. with no way to get at the coil i turned the air cond on then dumped a large can of spray Lysol in the intake vent it worked great but the cars roof headliner fell off about a week later.


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## fbelec (Jul 12, 2018)

Soundchasm said:


> My mind is blown at the thought of a perpetually clean outside unit!! ;-)


shut off the air cond when mowing or raking


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## sportbikerider78 (Jul 12, 2018)

Well...I'm back from vacation and missed the CRAZY hot weather we had.  I was sitting in a lawn chair, in the water at our cottage..but wow..still hot.  Entire family got sick (me 2x) and it was not that relaxing.  

So....the AC tech called me yesterday and we are ON for Friday night.  That means I have to get all the lines run (not connected) today and run power.  This will be a busy night after work.  

It would be amazing to get these units running for the weekend.  I'm on cloud 9 just thinking about it.  I've always been sweating my a** off in this house.


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## sportbikerider78 (Jul 12, 2018)

fbelec said:


> soundchasm you must have been feeling sick when they were running. nice job. a short funny story i had my car air cond on and would get a little mold smell followed by a stuffed nose. with no way to get at the coil i turned the air cond on then dumped a large can of spray Lysol in the intake vent it worked great but the cars roof headliner fell off about a week later.


Your blower is easy to access in most cars.  Some have air filters.  Check there first.


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## begreen (Jul 12, 2018)

Thanks for the reminder. The Volt didn't come with a filter, but the car has several Buick parts including the filter box, so I dropped in a Buick filter. That was a couple years ago. I expect it's time to replace.


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## fbelec (Jul 13, 2018)

older car chrysler 5th ave. thought it would be a ton easier to try the spray. no filters back then.


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## sportbikerider78 (Jul 13, 2018)

Had to stop a bit short last night...2 of the 3 done but the last had a hornets nest hiding under the deck right were I needed to work.  Sprayed and will resume work this afternoon before the tech shows up.  

Will post pics before I button everything up.  I am leaving the linesets rather loose because he will need to flare and need wiggle room to work.


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## sportbikerider78 (Jul 14, 2018)

Had the AC tech over last night to get things rolling and we ran into a bit of a problem.

I am attaching 3 line sets to 3 units.  A 12k, 15k and 15k.  All of them have 3/8" gas line coming out the back and a 1/4" liquid line.  Here is the issue..the 15k's all have a 3/8" line with a 1" flare nut for 1/2" line instead of a 3/4" flare nut for 3/8" line.  So, everything was going well till we realized that my 3/8" line sets would not work for the 15k units. 

We looked in the manual and it seems (vaguely) that 1/2" linesets are required for 15k units.  The weird part is that on the back of the condenser unit there is only one place for a 1/2" gas line return.  Meaning that on at least one of the linesets, you would need to go from the head 3/8" to 1/2" and back to an adapter that gets you to 3/8" again.  All of the returns but 1 are 3/8". 

This isn't making sense to us, so we are calling Mitsubishi Monday when the tech line is open. 

I only see 2 possible outcomes.

1) I need 1/2" line for both of the 15k units. 
For the 1 line I will need an adapter to neck down to 3/8".

2) They say go for it and use the 3/8" (likely with some performance consideration) and I will need an adapter like this to go from 1" flare nut on a 3/8" line to a 3/8" line. 



Not gonna lie.  I thought I did my homework and this one really pissed me off.  Such is life. 

If someone can explain the logic of starting at the head unit with 3/8 line, then immediately going to 1/2 for the line set length, then back to 3/8 at the condenser, I'm curious.


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## sportbikerider78 (Jul 14, 2018)

This is the correct mating flare connection coming out of the 12k.  3/8 mating to 3/8  No problems here.



15k head unit with 3/8 line coming out of it but 1" flare nut for 1/2" line.  That's the issue.


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## fbelec (Jul 15, 2018)

i don.t blame you for being pissed off. seeing that i;d be 4 feet off the ground too. how many indoor units will it handle? that even tho it's using small pipe it might be for a bigger line set for a unit that is more than 15k btu. or they are smoking the crack pipe.


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## sportbikerider78 (Jul 17, 2018)

Called Mitsubishi.  Unfortunately I will need to replace 2 of the 3/8" lines with 1/2" lines.  It is what it is.  I will also need the adapter I posted a picture of.  There is a local HVAC supply that has their version of that fitting for $5 instead of the Mitsubishi $49 + shipping.  Love it.

Picking it up locally Thursday morning and need to reschedule with the technician.


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## Ashful (Jul 17, 2018)

At least it hasn’t been hot, or anything like that.


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## sportbikerider78 (Jul 30, 2018)

Well my friends friend (an AC tech) fell through..and caused me multiple delays..about 4 weeks.
I have the right adapter in house from a local shop.  I installed the Mitsubishi required 1/2" return lines and just got a quote ($~600) for a certified installer to come and finish the job properly.  Complete ferrule connections.  Full 24hr pressure test. Nitrogen purge and charge.  
Scheduling now.  Should be done shortly.  

All said and done, should have scheduled them from the start...hindsight 20/20 and all.


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## fbelec (Aug 1, 2018)

for him to be there twice 600 isn't bad


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## sportbikerider78 (Aug 1, 2018)

Installer stopped by today and they want to braze the ferrule connections and a few other things differently.  Was supposed to be complete tomorrow, now they are coming back Monday with 2 guys to complete it in 1 day. 

The tech seems very 'legit', so overall I'm happy, but darn...just want this thing running.

He complemented my install..so that was nice of him.


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## fbelec (Aug 2, 2018)

your so close. must suck just starring at it and it being so hot


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## sportbikerider78 (Aug 3, 2018)

I have a window unit stuck in a sliding door.  It's ghetto as all hell but i have no neighbors and it keeps me cool.


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## fbelec (Aug 4, 2018)

sportbikerider78 said:


> I have a window unit stuck in a sliding door.  It's ghetto as all hell but i have no neighbors and it keeps me cool.



good for you thinking like that. do what you gotta. did that in a rented camper brutally hot and humid and the trailer had no ac. called a friend said bring down the extra ac i had and a roll of plastic and of course more beer


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## sportbikerider78 (Aug 6, 2018)

It is running.  I am so happy!!

This is a great day to get a system running.  92F and crazy humid.
Been running for 2 hrs and the temps have house wide have gone frim 82F to 76F on a very hot day.  I'd say we got the right unit.   
I still have to clean up the way the linesets coming out of the house look, and get the covers on, but first I am going to run the hell out of it an make sure the condensation is running down the lines properly.  

The head units are on full blast (speed 4) and you can hear them...they sound like a normal HVAC system coming on.  On speed 1 and 2 you can't even hear them.  

The condenser is 10 feet under my deck from where I am typing and it is completely silent to me.  While standing above it on the deck, you can hear the purr of a condenser, but man, the locusts are louder than the condenser.  Very happy!  
Total bill was a little more than I was quoted, but only by $100.  Total was $700.


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## begreen (Aug 6, 2018)

Congratulations!! I think you're going to love this unit. It wouldn't surprise me if it also changed your burning habits. It's more efficient, easier and much cleaner to run the heat pump during shoulder season. Now that we are buying wood we have found out it's also cheaper!


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## sportbikerider78 (Aug 6, 2018)

begreen said:


> Congratulations!! I think you're going to love this unit. It wouldn't surprise me if it also changed your burning habits. It's more efficient, easier and much cleaner to run the heat pump during shoulder season. Now that we are buying wood it's also cheaper!


Thanks man!  I think you are very right! 

In 2 hrs it dropped the RH from 65% to 49%.  Can't wait till tomorrow morning when the system has stabilized at about 72F.

I know it is ridiculous, but I'm genuinely giddy like a kid on Christmas.  So much planing, hard work and time taken to get this going.


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## Tegbert (Aug 6, 2018)

sportbikerider78 said:


> My 42kBTU unit is on its way.  Shipped yesterday.
> 
> I will have 15k head, 15k head and a 12k head unit.
> 
> ...



I have a question about this. Why did you match the outdoor unit with the indoor unit total btu? I was always under the impression that you could take the indoor units total to 150% of the outdoor.  

I may have missed it but what size is your house and where are the head units at? 


Lopi Rockport
Blaze King Ashford 25


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## sportbikerider78 (Aug 6, 2018)

Tegbert said:


> I have a question about this. Why did you match the outdoor unit with the indoor unit total btu? I was always under the impression that you could take the indoor units total to 150% of the outdoor.
> 
> I may have missed it but what size is your house and where are the head units at?
> 
> ...


I went through this with the Mitsubishi tech.  Here is the explanation he gave me.
You can do that, but you will only get the amount of cooling at the head units the condenser is sized for.  With matched units on a day like today where it is 92F outside, I can run the entire system full bore and get 42k of cooling.

I actually bought a 2.5T/30kBTU unit with the intention of running 42k of head units.  The cost to upsize to a 42k condenser was marginal, so I sprung for it.  The issue would be on a warm day like today, when the head units are asking for more cooling then the condenser can provide.  I think you are right, you can exceed the head unit rating by a certain amount, but I had a very hard time figuring out what amount that was and there was no point in risking it.

My house is a long ranch. 1900sqft. 3 bedroom. 2.5 bath with very high ceilings 9-20'.  The head units are in family room, kitchen area and master bedroom, where my office is.  The other 2 bedrooms are off the family room and will have a unit, basically blowing cold air at their open doors.  Very easy to put a fan in their rooms to help move air.

Another reason I upsized the unit, was because I thought maybe I would add an additional head to the basement for heat in the winter and dehumidifying in the summer. That unit would have been rather small and occasionally used...I was thinking 9kBTU.  

(BTW...that 2.5T unit is in the box and for sale for what I paid..about 50% off list...PM me if interested)


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## sportbikerider78 (Aug 6, 2018)

Google maps isn't what it used to be...but this is the home and layout...very roughly.

Red dots indicate head units.


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## Tegbert (Aug 6, 2018)

I look forward to hearing your results with this. Especially in the two other bedrooms on how well they do. Although I suspect just fine since the master and room next to it both look like they point that direction. 

My house is also 1900 sqft but short ceilings just under or at 8’. This has caused me some headaches on what and how to place the heads and where. Not sure I or my wife would like to see the head units almost at eye level but dealing with duct work for the ducted versions doesn’t seem to appealing either as far as matching size of duct work to what the static pressure of the blower is and what not. 

Decisions decisions. 


Lopi Rockport
Blaze King Ashford 25


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## sportbikerider78 (Aug 6, 2018)

Tegbert said:


> I look forward to hearing your results with this. Especially in the two other bedrooms on how well they do. Although I suspect just fine since the master and room next to it both look like they point that direction.
> 
> My house is also 1900 sqft but short ceilings just under or at 8’. This has caused me some headaches on what and how to place the heads and where. Not sure I or my wife would like to see the head units almost at eye level but dealing with duct work for the ducted versions doesn’t seem to appealing either as far as matching size of duct work to what the static pressure of the blower is and what not.
> 
> ...


I believe you have to leave the units about 3" of clearance above them, as that is the intake.  So..not quite eye level, but I know what you mean.

I think the big thing is just getting the humidity down.  Even 75F really is ok, if it feels dry.  A fan in the room does quite a bit then.


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## peakbagger (Aug 6, 2018)

Yup, life will be good. Now you need to figure out all the icons on the remote. I tend to run humidity control on really damp days and the temps drift down anyhow.  

Even though they are primarily a cooling unit for you, you will be impressed when you need little heat in shoulder season.


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## sportbikerider78 (Aug 6, 2018)

peakbagger said:


> Yup, life will be good. Now you need to figure out all the icons on the remote. I tend to run humidity control on really damp days and the temps drift down anyhow.
> 
> Even though they are primarily a cooling unit for you, you will be impressed when you need little heat in shoulder season.


I have had a Looooonnngggg time to figure out the remote.  LOL

I'm setting the temp at 70F, the fan on auto and telling the wifey not to touch it.  

Now, I'm thinking about the home that i'll be building out in the Albany, NY area when we move there in the next 6 months or so....I'd love to have one of these units in a new construction.  That would be pretty awesome. 
Now i'm thinking about all the different heating options that I'd need for the coldest part of the winter.  Wood obviously, is my go-to.  But what would complement this system well for heat when it is <30F?

I'm just daydreaming about the next house...my current one has a new oil boiler.  All set there.


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## Ashful (Aug 6, 2018)

sportbikerider78 said:


> I have had a Looooonnngggg time to figure out the remote.  LOL
> 
> I'm setting the temp at 70F, the fan on auto and telling the wifey not to touch it.
> 
> ...


Congrats, sports.  I remember when I got central AC finally installed in my first house, after 35 years of suffering these mid-Atlantic summers, like you it was a minisplit.

Last week, I spoke to one of the system experts at our largest local plumbing and HVAC installation company, about wanting to install a heat pump water heater.  He took at look at my setup, and said he wouldn't change a darn thing.  He cited the recovery time remorse many have with HPWH's, and how efficient my boiler and boilermate system are.

I'm still going to do the HPWH, mostly because the boiler running all summer makes our basement rec. room too warm for the kids, but my point is that sometimes it's hard to beat the horsepower of a boiler.  You know I have quite a heat load, here, and that little boiler in the basement has no trouble carrying 100% of it in the coldest of weather.

I'm a big fan of having a boiler with hot water for heat, and a separate AC system for cooling, but this has a high up-front cost.  All of my neighbors went with ground source heat pumps, as their sole heating, in much newer houses.  Of course, they each seem to experience a failure once or twice each year on much newer hardware, whereas we're always warm with our 30 year old boiler.


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## fbelec (Aug 7, 2018)

you did the right thing by matching the units to the compressor. and you find that out on a screaming hot day and you have a load of people over and the kids open and closing the door. if it were small your temp would climb and everybody would be uncomfy


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## Soundchasm (Aug 7, 2018)

The great thing here is that you did the right thing for the structure.  I always try to look at the "long" side of things.  It cracks me up to no end that in 200 years, somebody is going to be cursing me for the oaks that I've planted.  In the short-term, somebody is going to be THANKING you for your foresight with these mini-splits.  Good job!  Even if you don't benefit directly from this, your experience will help you in the future and be a BIG help to future residents.  You gave your neighbors a gift and they don't even know it!!  ;-)


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## peakbagger (Aug 7, 2018)

Once you get the humidity out of the air, 70 degrees is going to feel appropriate for hanging meat . I like it cool and usually have mine set at 75 F.

I heat my small fairly tight house down to 30 F with a one ton minisplit. If the sun is out, I can go down to 20 F. Anything lower and its pushing it.

I would be tempted to put in one of the picture frame or ceiling cassette units in new construction.  I dont think they move the air around as well but they are visually less intrusive.


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## maple1 (Aug 7, 2018)

Picture frame? Is that something new?


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## Ashful (Aug 7, 2018)

peakbagger said:


> Once you get the humidity out of the air, 70 degrees is going to feel appropriate for hanging meat . I like it cool and usually have mine set at 75 F.
> 
> I heat my small fairly tight house down to 30 F with a one ton minisplit. If the sun is out, I can go down to 20 F. Anything lower and its pushing it.
> 
> I would be tempted to put in one of the picture frame or ceiling cassette units in new construction.  I dont think they move the air around as well but they are visually less intrusive.



Ditto, on all three of your points.  My barn mini split fails to keep up heat at anything below 15F, and it sucks an enormous amount of energy just trying.  It’s great above 25F, though.  We usually see two or three weeks between single digits and teens each year, and often four or six nights sub-zero, I just eat the cost those few days each year.  

On cooling, since ours is going 24/7 from May thru September, we have basically no indoor humidity.  The house feels comfortable around 75 - 76, if you’re wearing shorts and tee shirt.  That’s good for sitting and watching the TV, but not for working hard.  I turn the shop down to 70F, when I’m working out there.


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## Ashful (Aug 7, 2018)

maple1 said:


> Picture frame? Is that something new?



There are several types of mini split indoor units that can be concealed within walls or ceilings.  All you see is a register, which can look like traditional AC.  These are for new construction, they’d be a difficult retrofit.  

Of course, I’d probably not choose a minisplit for new construction, their primary application is retrofit.


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## maple1 (Aug 7, 2018)

Ashful said:


> There are several types of mini split indoor units that can be concealed within walls or ceilings.  All you see is a register, which can look like traditional AC.  These are for new construction, they’d be a difficult retrofit.
> 
> Of course, I’d probably not choose a minisplit for new construction, their primary application is retrofit.



Yes, I had seen some. But not remembering something resembling a picture frame. The ceiling cassettes had me quite interested until I found they won't fit between 16" joists. You need 24" OC. Or all the ones I saw at least - I have a spot in a first floor ceiling where one would do very well, if it would fit. I will have to check them all out again to see what's new in the last couple years, if anything. I think I almost have wifey convinced, she has been dead against them from the get go for some weird kinda reason - but she did ask last month about how much they cost. We don't have very many spots where a typical high up wall mount would fit very good, it seems.

I would definitely consider a minisplit for new construction, almost seems a no-brainer in my mind. It's being done a lot around here now. We don't have NG though - that might make a difference.


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## Ashful (Aug 7, 2018)

maple1 said:


> Yes, I had seen some. But not remembering something resembling a picture frame. The ceiling cassettes had me quite interested until I found they won't fit between 16" joists. You need 24" OC. Or all the ones I saw at least - I have a spot in a first floor ceiling where one would do very well, if it would fit. I will have to check them all out again to see what's new in the last couple years, if anything. I think I almost have wifey convinced, she has been dead against them from the get go for some weird kinda reason - but she did ask last month about how much they cost. We don't have very many spots where a typical high up wall mount would fit very good, it seems.
> 
> I would definitely consider a minisplit for new construction, almost seems a no-brainer in my mind. It's being done a lot around here now. We don't have NG though - that might make a difference.



It’s hard to argue with the economics of a ducted system, for new construction.  This is why we mostly see minisplits as retrofits, around here.

As I understand it, the biggest issue with retrofitting the ceiling units into existing construction is drain line routing.  They’re apparently fairly sensitive to drain line slope.  Also, at least back when I was shopping them, the Mitsubishi ceiling units could not do heating, only cooling.


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## peakbagger (Aug 7, 2018)

I have not had an experience with either one of them, either ceiling cassette or picture frame but have seen glossy pictures of them  The picture frame has artwork in the middle surrounded by louvers that look like picture frame. With both of them I expect the performance is impacted.


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## fbelec (Aug 8, 2018)

i've wired the ceiling and wall type i think the ceiling cass is way more visible and normally mounted in the center of the room that screws up installing a ceiling fan..i wired a apartment with the ceiling cass. 2 for heat and a.c. takes less power than your everyday duct style. don't forget that the conv. duct style has very high seer ratings now 21 22 and higher. if doing a new construction central heat there is dual fuel furnaces. very efficient


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## maple1 (Aug 8, 2018)

Did some quick googling and I only found LG 'picture frame' units. When we take the plunge it will either be Daikin or Mitsubishi - I think I have gotten that part decided at least. I don't think they have changed much on their inside unit offerings since I was looking heavy a couple years ago.


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## peakbagger (Aug 8, 2018)

One other option that is fairly new is an air to water heat pump. It looks like a minisplit but the refrigerant is all in the outdoor air unit so need to have someone charge it. http://www.americansolartechnics.com/products/space-heat-pumps/

It heats or cools water or glycol which is pumped out to the unit. There is no standard indoor head unit but it could go to a duct mounted coil or coil in an enclosure with drip pan for cooling. Ideally if the house has low temp radiators/emitters it just plumbs into the heating loop for heating.

Radiant cooling is an up and coming method of cooling, the problem is unless the controls are right on, dew point issues can be a real problem. In the damp weather conditions we have been experiencing of late I expect it would be big issue unless there is humidification done on the makeup air.

Tom In Maine on Hearth has the most experience with these as he is the one importing and selling them. John Seigenthaller had mixed comments when I took a heating course. He liked the concept but his experience with one particular brand wasn't great. Tom claims to have gone through a couple of suppliers until he got a reliable brand and I am not sure if the one John had experience with is that same as that Tom is selling.

If I was starting from scratch and didn't own a regular minisplit and had low temp radiators/emiitters or radiant tubing it might be nice option to consider but would require a lot more design on my part to get the cooling side right.


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## Highbeam (Aug 8, 2018)

The air source heat pump water heater from tom above would be a great idea and the specs are great but it’s some Grey market Chinese thing with no brand reputation. We’re talking several thousand bucks for this thing.

It won’t be long and we’ll see the co2 systems that can heat domestic water and replace boilers in hydronic heat systems.


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## sportbikerider78 (Aug 9, 2018)

Crazy humid this week.  The system isn't working much to cool because the temperature differential between inside and outside isn't much.  We will try the humidification feature today, as the humidity is climbing because the system isn't running much.

This is our 3rd full day on the system and we couldn't be happier.  I'll tidy up all the linesets in the next few days and post final install pics.


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## Ashful (Aug 9, 2018)

Depending on the characteristics of your house, sometimes switching from auto fan to fan always on can make a big difference on days when it is not hot enough to make the thermostat cycle the unit on a reasonable time constant.


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## begreen (Aug 9, 2018)

sportbikerider78 said:


> Crazy humid this week.  The system isn't working much to cool because the temperature differential between inside and outside isn't much.  We will try the humidification feature today, as the humidity is climbing because the system isn't running much.
> 
> This is our 3rd full day on the system and we couldn't be happier.  I'll tidy up all the linesets in the next few days and post final install pics.


Happy for you man. It's great when a plan comes together.


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## sportbikerider78 (Aug 9, 2018)

Ashful said:


> Depending on the characteristics of your house, sometimes switching from auto fan to fan always on can make a big difference on days when it is not hot enough to make the thermostat cycle the unit on a reasonable time constant.


It seems like auto just leaves the fan on all the time as well.  I haven't noticed it turning off at all.


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## Ashful (Aug 9, 2018)

sportbikerider78 said:


> It seems like auto just leaves the fan on all the time as well.  I haven't noticed it turning off at all.


Yeah, I have two Mitsubishi minisplit systems, and they do the same.  Heck, I've had Mitsu minisplits for about eight years now, and I still can't figure out what they're doing most of the time.  There's no clear cause/effect relationship to my control inputs and system behavior, like a traditional system, but they do work!  My comment reflects more the behavior I get from my traditional system, where switching the fan to manual increases comfort on days when the system might cycle insufficiently on an "auto" setting.


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## sportbikerider78 (Aug 10, 2018)

Ashful said:


> Yeah, I have two Mitsubishi minisplit systems, and they do the same.  Heck, I've had Mitsu minisplits for about eight years now, and I still can't figure out what they're doing most of the time.  There's no clear cause/effect relationship to my control inputs and system behavior, like a traditional system, but they do work!  My comment reflects more the behavior I get from my traditional system, where switching the fan to manual increases comfort on days when the system might cycle insufficiently on an "auto" setting.


It could be just that the auto keeps the fan circulating (seems like speed 2) and never any slower.  I suppose it has to do that in order to better air sample.  
I'm not sure what type of sensor is on the outside of it, but I have also noticed that the one in a bigger room runs speed 2-3 continuously on auto with the same settings.  
Maybe they are smarter then I am giving them credit for.


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## Ashful (Aug 10, 2018)

I have the MHK thermostat (external wall mounted with auto-change-over) on each of mine, and even with the sensor switched to the remote thermostat (an option you can control), it keeps that fan turning almost all the time.  There’s intelligence built in there, but they don’t do a great job of explaining the behavior, for inquiring minds.


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## CaptSpiff (Aug 10, 2018)

Ditto the LG. I never ran the "Dehumidify" mode because I didn't understand what "its" thinking was. No explanation in the owners manual. Finally stopped at the LG booth at an HVAC show and the Tech explained that "it" measures the incoming air temp and adjusts the coil temp to maintain a fixed lower temp. He said it maximizes the moisture removal and still "cools" the output air,... just not so much. Now that's my go to setting for when I'm not home.


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## sportbikerider78 (Aug 13, 2018)

I tried  the setting.  Felt just like blasting the ac.  Maybe I'm wrong, but it sure cooled the place down and dried it out.


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## peakbagger (Aug 13, 2018)

I run dehumidify when first turned on in humid weather for a few hours until the place dries out then I switch it cooling mode and set the fan on automatic.


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## nedjinski (Jul 23, 2020)

Considering using a mini split system in a single large room house for the purpose of supplemental heating and cooling - not as a primary source for heating or cooling. I have a wood stove that I would continue to use and I want to cut down on the amount of wood I need every year. In the summer the room might go above 75 once in a while and I would like the ability to cool the room down but only when that happens.
Does a mini split system make sense? and can it work effectively as a supplemental system?


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## peakbagger (Jul 24, 2020)

nedjinski said:


> Considering using a mini split system in a single large room house for the purpose of supplemental heating and cooling - not as a primary source for heating or cooling. I have a wood stove that I would continue to use and I want to cut down on the amount of wood I need every year. In the summer the room might go above 75 once in a while and I would like the ability to cool the room down but only when that happens.
> Does a mini split system make sense? and can it work effectively as a supplemental system?


Hard to beat your setup to use a minisplit for  supplemental heat. Run the minisplit during shoulder seasons when you need heat at night but it warms up during the day and keep running it until the temps drop to about 20F at night.


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## maple1 (Jul 24, 2020)

nedjinski said:


> Considering using a mini split system in a single large room house for the purpose of supplemental heating and cooling - not as a primary source for heating or cooling. I have a wood stove that I would continue to use and I want to cut down on the amount of wood I need every year. In the summer the room might go above 75 once in a while and I would like the ability to cool the room down but only when that happens.
> Does a mini split system make sense? and can it work effectively as a supplemental system?



Yes, absolutely.  Not sure exactly how cold your climate is, but it could even end up being your primary source, and your stove secondary. But once you have one, and another heat source, you have lots of flexibility on how to run things.

I would only do a cold climate (high efficiency) model. Any price premium is way worth it.


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## peakbagger (Jul 24, 2020)

I agree with Maple, go with a cold climate unit. Check with your utility they may give you a rebate.


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