# Mini Split AC



## bpirger (May 9, 2015)

Yes, off topic...but I can't resist. 

Is it as easy as it seems to install a mini-split AC system?  Gettings quotes for well over twice the cost of the hardware (30K BTU single room unit...) and I just can't get myself to hand over $2500.  If I can plumb the Garn and all the radiant, then I suspect I can do a fine job with the minisplit.  I'll try and get a pro to come over and evacuate the lines and do the final checkout for warranty purposes.

This "line hide" monstrosities on the outside of the house is very ugly....but very easy.  Mounting the unit inside, drilling the hole, and connecting the flared couplings seems straight forward.   It seems to me like a skilled crew of two can do it in just half a day, no?  Or less if things are short and readily available (like power at the compressor, pad, etc.)

Any recommendations on units or units to avoid?  I'll like go with the heating ability, as I could throw a little heat upstairs as I STILL don't have my staple-up and panels in upstairs.   Any strong preference in brand or technology?  Seems like everyone goes with the inverter technology now...Mitsubishi, daikin, Panasonic, LG, lennox, blah blah blah.   I don't need the hyper heat....really just want the cooling.

I have a 24K in the window unit upstairs that I have used for the whole house for years.  But as I put up  the log siding, I really prefer to rid myself of the ugly "shelf" holding the unit up in the window.   The window unit did a decent job on the whole 2500 sq ft of house....not cold, but 73 or so and quite dry furthest away on a 95 sticky day.  I'm thinking a 30K unit, in a slightly better upstairs location, should be even better.

I've paid one guy in this house building project, a stone mason, to install stone veneer on the foundation and low walls, and while it is DONE, unlike most other things, there is slanted stone and goofs that he wouldn't fix....and some serious cash out the door as well (like 4 x's the minisplit install.....and he did about 4 weeks of stone work....so that really drives home the crazy price (it seems to me) for the AC install). 

Any comments/suggestions/experiences welcome.  

Thanks,
Bruce


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## peakbagger (May 9, 2015)

There have been a lot of threads in the green room on this. A skilled crew of two can do it in less than 4 hours not including running the new circuit. It took me about 8 hours as I didn't have the right tools and was doing it solo plus I built a base out of unistrut for the outdoor unit. I agree that the line set cover is ugly but the alternative is opening up the walls. Its too bad as if the walls were open, it would be easy to preinstall a chase.  I did hire a HVAC contractor to purge and pump the lines.

The biggest issue to consider is that buried in the contractors price is essentially a service contract. Both Mitsubishi and Fujitsu sell through dealers only and the only way you can get warrantee repairs or replacement is through a local dealer, the factories have no method of dealing directly with consumers. Sure you can buy a unit on the internet from a dealer but they can sell at a low markup as they don't need to maintain a fleet of servicemen as they know that once installed, someone is not going to send it back and even if they do the dealer can argue a poor install.

I have talked to a couple of Mitsubishi servicemen and the units are basically not serviceable. The vast majority of the repairs are due to external damage like things hitting the external units.or tubing. They have several units on the shelf at the shop and after the initial service call the vast majority of the time they replace the unit and bill the owner for non warranty replacement. 

I and many others take the risk and buy them from the internet and do the majority of the install and then hire someone to do the final hookup. If you are only doing one, you can buy the pump and gauge kit but the one time cost is more than hiring a HVAC tech. It is worth doing it right. Many folks skip the argon purge or do a poor job on the flare fittings.


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## Ashful (May 9, 2015)

Have had a few installed, all Mitsubishi, and each have taken a crew of two 6 - 8 hours.  In each case, I supplied electric to the outdoor unit location.

I'm very impressed with the performance of the Mitsubishi units, so quiet (both inside and out) it's hard to tell if they're running.  One of mine ran just fine in heating mode thru the last two pretty horrible winters, never dropping out.

I run the line sets inside, where possible.  Just make sure you have a lot of slope on the drain, as the installers and service guys say they see backups on the ones without aggressive slope.


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## flyingcow (May 10, 2015)

I'd recommend not hanging the units off the outside wall. Make a base to set it on. If hung on the side of building, they will cause a slight noise/vibration in that corner of house.


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## Thenewguy (May 10, 2015)

I would highly suggest mitiubishi. They have strong units and a very good customer services for techs and homeowners a like.   Make sure you lube your flares with a vacuum or refrigerant oils don't use any type of pipe dope on the flares. As the dope breaks down there's a very good chance of it clogging up the expansion device and 5 to 10 years.  Make sure the unit you buy is sized correctly undersized and it will never cool down the house and over sizing the unit can create short cycles with a cold house but lots of humidity.  Make sure both lines are insulated for best efficiency 

It's to bad Ithaca is a bit far for me I'd do the start up for you myself.


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## Ashful (May 10, 2015)

Makes me feel good about switching HVAC companies, when the company I used for my first Mitsubishi went and switched to installing York.


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## DougA (May 10, 2015)

I installed my own split a few years ago. I thought I was going to save a ton of money but I still had to get a service tech in to purge the line and install the refrigerant because I needed an extended line. Worked great for 2 yrs but now the unit gives me a code saying there is moisture in the line and the service guy did not put a filter on the line so it has to be re-done. At that point, it will be the same price as having someone do the whole job for me.


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## Thenewguy (May 10, 2015)

What brand mini split is it. Most condensing units have a filter dryer built into the condenser and are not designed for another filter to be installed and can restrict flow to much.  It's possible tht you have a ba sensor or the installing tech didn't fully evacuate the system upon startup. Bein that it's a closed system moisture doesn't just get into the line sets.  Also if it's not a bad sensor. Make sure the existing filter dryer is removed and install a new one.  And that 100% new refrigerant is put back into the system.


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## STIHLY DAN (May 10, 2015)

DougA said:


> I installed my own split a few years ago. I thought I was going to save a ton of money but I still had to get a service tech in to purge the line and install the refrigerant because I needed an extended line. Worked great for 2 yrs but now the unit gives me a code saying there is moisture in the line and the service guy did not put a filter on the line so it has to be re-done. At that point, it will be the same price as having someone do the whole job for me.



There is not supposed to be a filter, there is no liquid line. You cannot over size with the inverter technology. I like them mounted on the side of the house, keeps them out of the snow and really helps keep mice out of the unit in the winter.


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## Thenewguy (May 10, 2015)

Not all units use inverters it depends on brands and models.  An there is still a filter built inside the condenser


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## peakbagger (May 10, 2015)

I am not thrilled by the wall mount hangers sold for the units. I made a much beefier version out of unistrut and made sure to by some vibration isolation feet. My house is 6" walls 16" OC and I really haven't noticed any vibration from the outdoor unit. The base of mine is 4' up off the ground and I still ended up doing a bit of shoveling under it this winter. I also strongly recommend a 12/12 pitched roof over the top of the unit to keep snow off if it. Make sure it has at least 6" of overhang and leave a good sized gap above the unit to let air circulate.


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## maple1 (May 10, 2015)

Anybody just set their outside unit on a deck?


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## velvetfoot (May 10, 2015)

maple1 said:


> Anybody just set their outside unit on a deck?


I'm thinking under the deck for shading and snow.


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## Thenewguy (May 10, 2015)

You could set it on a deck. But you would have to clear snow for heat efficency. 

I agree with peak nagger if you go wall mounted use vibration isolaters.


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## maple1 (May 10, 2015)

I guess I was thinking more like a verandah. Its screened in in the summer, minimal snow in it in the winter. Well, except for this past winter. Seems like the best spot I can think of to put it here, proximity wise.

I think there is one of these things in our future - summer AC for starters, but also maybe some shoulder heating if I'm feeling like a break from burning wood.


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## Thenewguy (May 10, 2015)

You may get to much heat build up if it is to closed off of a area. Also the noise of the unit maybe a nuisance .


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## STIHLY DAN (May 10, 2015)

Thenewguy said:


> Not all units use inverters it depends on brands and models.  An there is still a filter built inside the condenser



How many of these are you putting in? Non inverter units are dinosaurs technology wise, Personally I would not install one of those for anyone. They are so much noisier, and inefficient. I actually haven't seen a non inverter installed around here since 05. I did see some cheapy internet do it yourself ones a few weeks ago. They actually have a plug to plug the condenser in to an outlet. 3yrs old, 1 has a blown compressor do to no refrigerant. The other has a blown board in the condenser, looks like it was on fire. You get what you pay for.


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## Thenewguy (May 10, 2015)

I typically install 5 to 20 ductless splits a year. I do primarily construction install so the architects and engineers tell me what they want installed. Although I highly suggest installing inverter units. You can still buy non inverter units as well. And we install about 50/50 of each.

Although I apologize this is way off the posters original topic.


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## BrotherBart (May 11, 2015)

Thenewguy said:


> I agree with peak nagger if you go wall mounted use vibration isolaters.


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## Thenewguy (May 11, 2015)

BrotherBart said:


>


Make sure you use the right mounting hardware as well. LOL


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## bpirger (May 11, 2015)

Have another quote coming from another local company.  He said $2500 on top of the materials was nuts....agreed two guys less than a full day.  So there is hope.  It's interesting...this fellow was an older guy...and without a doubt he spent decades working in the trenches in the HVAC business and now he's doing estimates for AC during this peak time (been very hot here....high 80's....maybe spring will come later this week).  Very knowledgeable and not trying to sell me something.  He took down some numbers to do a heat load, looked around, chatted for a long while, and said he'd MAIL me the quote in the next couple of days.  We got him to do email.....LOL.  He didn't tell me BS like the last guy....indicated he wasn't sure if he didn't know.  The last guy told me, when I asked, if I put the remote in the freezer if the AC would ever turn on...now he said.  LOL   So, there's quite an enormous difference between a salesman and a guy with decades of experience providing a quote!  I know which one I prefer.

We talked about me installing and them sending a guy out to evacuate the lines and top off the refrigerant.  He says they do it all the time....no problems.  Then he proceeded to tell me about the things to be careful of.  What more could you ask for?

So the quote will come in a couple of days and hopefully it will be good enough for me to let them do it.  Else maybe I can buy the hardware from them and have them come out in a week.  He said his prices were comparable to the internet....so he's very aware.  These are the kind of guys I want to have on my side for sure. 

These folks install Mitsubishi.  We talked about the others and he said likely they are all very similar these days, but he doesn't really know as he hasn't seem other than mitsu.  He flat out says he always asks the mitsu rep why they get a little more, how their stuff is better, and he smiles and said he's never heard a reason.  Mitsu comes out with something and everyone copies it the following year.  We agree that everything is likely built in China anyways...

I also had the driveway repair guy show up today.  Yikes.....when did gravel become so expensive?   I need many loads on the 900' through the woods craziness...well beyond the other companies crazy AC quote.   But without a doubt, looks like I need to turn some of that labor into gravel.

Thanks guys.....leaning towards the mitsu system.  Unless something falls from the sky, it seems like the way to go for us.  Thanks!


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## STIHLY DAN (May 12, 2015)

The ac will turn on if the remote is in the freezer. Mitsu is the top of the line.


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## flyingcow (May 13, 2015)

STIHLY DAN said:


> The ac will turn on if the remote is in the freezer. Mitsu is the top of the line.




Or put it in the oven.....in the winter. The heat will still come on.


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## bpirger (May 14, 2015)

Of course it will, but the salesman who came out to give a quote said otherwise.  It's just funny they don't know how their stuff works.  The remote is used to set a point, which is then sensed on the incoming air to the evaporator unit, not by the remote itself.  He was telling me the remote was providing feedback, like a real thermostat, which would imply some type of RF (not line of sight) communication.   Completely possible of course, but completely wrong.

Other quote still came back high....little lower than the other guys for a 30K Mitsu vs. the 24K Daiken.   But, I think I am going to go it alone and call them for the final turn on.  Depending on how much I spend, I will likely buy a manifold set and pump.  Throw in the micron guage and I could have the whole show ready to go when they arrive.   Even with buying the $600 or so in tools, I'm still well over $1K ahead.   That's a few loads of gravel, plus everything I need to keep it going in the future, not to mention installing a second system someday in the addition.


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## peakbagger (May 14, 2015)

I actually bought a pump at one point and a manifold but for $250 to have the local pro flare, purge and pump the lines, I decided to have him do it. I have an out of warranty Mitsubishi AC only unit that I may be replacing with cold climate mini split, I expect that one will be something for me to play with.


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## STIHLY DAN (May 14, 2015)

bpirger said:


> Of course it will, but the salesman who came out to give a quote said otherwise.  It's just funny they don't know how their stuff works.  The remote is used to set a point, which is then sensed on the incoming air to the evaporator unit, not by the remote itself.  He was telling me the remote was providing feedback, like a real thermostat, which would imply some type of RF (not line of sight) communication.   Completely possible of course, but completely wrong.
> 
> Other quote still came back high....little lower than the other guys for a 30K Mitsu vs. the 24K Daiken.   But, I think I am going to go it alone and call them for the final turn on.  Depending on how much I spend, I will likely buy a manifold set and pump.  Throw in the micron guage and I could have the whole show ready to go when they arrive.   Even with buying the $600 or so in tools, I'm still well over $1K ahead.   That's a few loads of gravel, plus everything I need to keep it going in the future, not to mention installing a second system someday in the addition.



The older units had a pin hole to press that would tell the head or the remote to sense temp. Mitsu will cost more than a daikin, but for a do it yourself install Mitsu has an online web page for help.


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## davem3261 (May 16, 2015)

How big of a room is this going in?  I put an 18k Mitsubishi  in my parents living room and that room is huge.


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## bpirger (Jun 23, 2015)

Just as an updated....completed the installation of the 2.5 ton Mitsubishi unit yesterday and now have a cooled house.  I did the vast majority of the install myself, paid the tech to come out pressure test and evacuate the lines.  Everything was fine, no leaks, and so far no problems....been running 24 hours.  Saved just about $1800.

Nothing really tricky about it.   decided not to buy the pump and gauges....now I have a relationship with a knowledgable guy should any problems arise.

Appears to be cooling the entire house quite well.  Nominally 2500 sqft....very open....two floors at the moment (great room covered with "temporary floor"....going on 14 years temporary....until T&G pine hung on ceiling above).   88 outside yesterday, about 65 upstairs (where the unit is high on the wall) and never over 72 down stairs.  Just what we wanted I think.

Thanks!


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## Ashful (Jun 23, 2015)

Finalizing install of another two Mitsubishi units on my carriage barn, this Friday!  Also using a pro for final setup.


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## velvetfoot (Jun 23, 2015)

bpirger said:


> Just as an updated....completed the installation of the 2.5 ton Mitsubishi unit yesterday and now have a cooled house.  I did the vast majority of the install myself, paid the tech to come out pressure test and evacuate the lines.  Everything was fine, no leaks, and so far no problems....been running 24 hours.  Saved just about $1800.
> 
> Nothing really tricky about it.   decided not to buy the pump and gauges....now I have a relationship with a knowledgable guy should any problems arise.
> 
> ...


So, you have one fan unit (or whatever it's called) on the second floor?


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## bpirger (Jun 24, 2015)

Yes, just one inside condenser unit on the wall, high up in the peak.  It's about 11' up from the upstairs floor (gambrel roof inside....14' peak  from the second floor...25' peak from the first floor).  Upstairs is mostly open.  Downstairs is also mostly open....but it actually does a really decent job everywhere.  30000BTU (2.5 ton) unit...single compressor (HUGE at about 3'x3'x14" thick...compared to what you typically see behind a house) and single indoor head.  5/8x3/8 line set 31' long.  Looking forward to hot humid weather just to see how it does when its 95 and 90%.


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## Ashful (Jun 24, 2015)

Surprise... they showed up a few days early.


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