# Windowless A/C?



## cbrodsky (Jun 20, 2007)

In line with another thread, I am a big fan of window A/C over central A/C.  My A/C system cost $88 x 2 for two 5000 BTU units, and I rarely have them both run, and one only runs about one month total over the season in our climate.  Sure beats the $8K our builder wanted for a dual-zone central A/C.

However, I wouldn't mind something easier to install/remove, and potentially quieter compressor noise.  I have debated trying a windowless unit for ease of install/removal each year, as well as the fact that it looks much better.  Additionally, some seem to be rated for much lower dB as compared to a window unit.

Anyone have experience with something that would be considered an ultra quiet "high end" window unit and/or windowless unit that would be a good one to consider as an upgrade to meet these requirements?  Obviously I still want to be efficient and will pay more for it, but I think most any 5000-10000 BTU solution will be far better than a central A/C by avoiding duct losses, thus I'm willing to consider a windowless even if not as good as a window unit in terms of raw efficiency.

-Colin


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## GVA (Jun 21, 2007)

You could try one of these...   http://us.sanyo.com/industrial/HVAC/features.cfm
We have them in the server rooms at work (which get pretty warm) and in the humidor at our distribution center.

The condenser unit is like a 10th the size of a full house unit and the inside wall mounted unit is about 10" tall 3' wide by 4" deep.
It even comes with a remote.......
They are pricey though......  But excellent for zone cooling.


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## Mo Heat (Jun 21, 2007)

Well, that's certainly an interesting product, but it seems like a stretch to install at my place. My central A/C unit has had to be recharged with freon the last two years. Four pounds last year, and two pounds this year. I guess I'm polluting, but what can I do? The A/C guys don't want to sniff out the leak, and frankly, it's cheaper to just charge up and worry about it next year.

I've inquired about a new 5 ton central unit and got a ballpark figure of $5,000. That 3 room Sanyo unit costs just about the same. I know I'd save some money just cooling 3 rooms, but the rest of the house would be hotter than hell. In the winter, I can get around this using an electric panel heater in the kitchen and basically abandoning several other rooms that don't see a lot of action anyway. But in the summer, I'd need to install another one of these in the kitchen. For that kind of money, it's a lot cheaper to go central.

Am I missing anything obvious?


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## begreen (Jun 21, 2007)

There are several split systems out there. In some countries this is the predominant type of AC. While we were in Hawaii we got to try one out and they are very nice. They use super efficient compressors and are very quiet. Sanyo, Panasonic, Mitsibushi make nice units.


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## cbrodsky (Jun 21, 2007)

These are interesting and I've stayed in hotels with them - usually on islands with high power costs.  What is interesting to me about these is that they call them "zoned" and suggest you need one in every room.  However, I'm cooling my entire house 99% of the time using a 5000 BTU window unit in the middle upstairs area.  Fairly open floorplan so it dehumidifies and cools the whole house relatively well.  If I come home and it's 78 in the house, it'll take a few hours to get to 72, but if I let it run on it's thermostat all the time, it holds the temp well enough and I feel this is better to many units cycling on and off all the time.

I would think one 10,000 BTU unit, centrally located, would be plenty adequate and would give us more capability to cool down quickly when needed.  I believe that is equivalent to a one-ton conventional central air unit - not sure if they even make such a thing.

I do have one other option.  We weren't sure just how much we'd need A/C, and keeping a mind to eventual resale, we did have ductwork put in that is currently unused.  (wood w/oil HW backup for heat)  My guess is that if we could find one of these split units or something compact with say 3 duct connections, we could get more than adequate balanced cooling throughout the house even better than what I have today, with a minimum of duct connections and losses.  (could insulate the heck out of the 3 that would be in use)  If I had known how well shaded and insulated the house was, I never would have had them do their standard install with what must be 20+ ducts.  It's just overkill, tons of places to leak if I used them all, and I'm sure if I ever got central A/C put in, it would similarly be total overkill on the sizing.

-Colin


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## cbrodsky (Jun 21, 2007)

for example... 

http://us.sanyo.com/industrial/HVAC/Concealed_Duct/Air_Conditioners/index.cfm?productID=1286

Rated 15 SEER which I think is pretty darned good, and looks like you can connect up 3 ducts.  I think my house built in 2000 in Austin was 11 or 12 SEER.

-Colin


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## begreen (Jun 21, 2007)

I looked into the biggest Sanyo concealed duct heat pump for our house. Almost went for it. They are super efficient and very quiet. But none of the firms I contacted had ever installed one, almost all hadn't even heard of them. Yet in India this style unit was quite popular. They are nicely made too. I looked inside at the wiring in the Sanyo. Neatly harnessed and well labeled. The American Standard unit we have looks like a rats nest inside.  I think we're stuck with some ludite technology here that will be replaced soon by foreign technology unless American companies wake up and realize this is just like the automotive industry.


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## keyman512us (Jun 21, 2007)

NYSoap and all...
Good discussion all the way around. I know where you are coming from. Your thoughts closely mirror my own. I'm a big fan of the 5K window units also...but have considered the compact units as well. Everyone is bringing up good points. The only thing I would add about the situation, in a "couple few years" I'm sure the evolution of these units is going to happen. Needless to say, don't rush, do your homework and... actively seek out "new" contractors leaning to these units. If none are available, do a little research, contact some different manufacturers and say "Hey I want this, make it happen... set me up good and I'll provide a good testimonial for you." Work with the manufacturers trying to get their product recognized... you might be surprised. Perhaps we could get Web to look into getting us a "group discount"...lol Would make quite the commercial "How SMART Wood burners stay comfortable in the off season"...lol
 Something I would like to see the "cooling industry" progress to, and it will probably be a foreign company to get the ball rolling rather than Trane, Carrier or American Standard... Would be to utilize the "waste heat" from central AC, compact units..or even window units for heating or at least "pre heating" domestic hot water. American homes are terribly inefficient if you really look close. An idea I have been "working on" is a basic all around dual role, AC, air exchange,DHW pre heater and dehumidifier. I'm not going to get into the particulars...it's a rainy day project...lol

Suffice to say...just don't get aggravated...be prepared to do some homework and in time...you will find the best idea.


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## begreen (Jun 22, 2007)

This is pretty much the European pov, scavenge every last btu from the system. I hear ya Keyman, time America woke up and smelled the coffee.


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## webbie (Jun 22, 2007)

My (newer) house here has central air, but 3 zones using dampers in the duct and separate thermostats. It is quite inexpensive to operate......of course this year we don't (yet) have to operate it at all. The breeze outside today feels just like AC.

In my last house I had to install two Frederick heatpump/ac units (they look like window units) into the wall when I built a large addition. We had hot water heat, so could not install central in that area. They did the job but the noise was unpleasant...especially in the bedroom. If I ever had to do it again, I would use a split system.....they were not readily available back then (1986). 

I am intrigued by those portable AC units.....not that I have a use for one, just that they seem very flexible if you are renting a place or need spot AC.


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## cbrodsky (Jun 22, 2007)

I was looking at these some more - it seems to me that this is not beyond the reach of a skilled DIYer except for charging the refrigerant lines.  (used to do that on my old car but all my equipment is for R-12!)  They seem much lighter weight and easier to work with compared to traditional central systems.

A lot of these things don't look that tough once you start reading the install manuals - maybe I'll consider going down that road one of these years and cut the costs considerably.

-Colin


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## sailor61 (Jun 22, 2007)

What experieince has anyone had with the mini-split AC systems?  They are permanently installed, remote compressor, no duct-work and in the middle of the cost between portable window units and true central.  An airhandler that is approximately 36 long, 10 hi and 8 deep is permanently hung on an interior wall, you do need to have access for 2 coolant lines and a condensate drain.  I've heard great things about them; mid level cost, efficiency of the compressor, no cooling loss from leaky ducts, quiet because compressor isn't hanging in your window.  And the cosmetic benefit of not having the thing hanging out the window.  Best of all - you can supposedly diy the install and then find a cooperative HVAC guy to come in and check the refrigerant charge.

thoughts?  experience?


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## Kilted (Jun 24, 2007)

Try:

Sharp portable; CV-P12LX  | Air Conditioners  11,500 BTU, EER 8.5 

http://www.sharpusa.com/products/ModelLanding/0,1058,1672,00.html

About $700 delivered off of the internet.  Very quiet, you can sleep next to one, I have one in my bedroom.  On low it is quieter than my window fan on low.

--  Brandy


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## velvetfoot (Jun 25, 2007)

We were at a restaurant yesterday that had a floor standing A/C unit with a plastic duct going outside.


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## Hogwildz (Jun 25, 2007)

My parents had 2 mini split or "ductless" systems installed in their house. Compressor outside, just a head in the wall. 3" hole is all that is required. Quite and very nice.
Gives a zone cooling effect. Nice system. Saved more electricity than the older wall mounts. Cost them about $6,000.00 for the 2 installed. More expensive than central, really only an option if you have no duct, or have money to spend.
 I had a guy out for a quote on central AC today. We'll see what comes back. Have an $8,700.00 quote from the last guy. I want the central because I am extending my duct to the addition. want to use same heater & ac for all. Beats buying separate furnace etc. Especially when the heat is only for backup. addition is still waiting for that new stove to add with the Summit insert for heating.

Regarding the "portable" A/C units. Don't waste your money. I have one in for repair not even a year old. Used 2 months last summer. They are no quieter than a window mount, more expensive ($499.00 for a 10k unit), and made overseas, junk & warranty work is a PITA. First repair company given by warranty co, said " We don't work on those pc's of chit". Second place is about 60 miles away. And had pretty much the same to say of these units, except he said it in a nicer manner.


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## Kilted (Jun 28, 2007)

Hogwildz said:
			
		

> Regarding the "portable" A/C units. Don't waste your money. I have one in for repair not even a year old. Used 2 months last summer. They are no quieter than a window mount, more expensive ($499.00 for a 10k unit), and made overseas, junk & warranty work is a PITA. First repair company given by warranty co, said " We don't work on those pc's of chit". Second place is about 60 miles away. And had pretty much the same to say of these units, except he said it in a nicer manner.



So would you mind naming the brand and model that has been so troublesome?  To paint all brands by one bad example is not very responsible.

Just so happens that with my style of windows I can not use the usual window units.  The Sharp unit I mentioned above is quieter than any window unit I have ever heard.  To condem it site unseen or "heard" is blaintly unfair.

I will recommend to any one to do your own research and do not blame all brands for one bad choice.

-- Brandy


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## Hogwildz (Jul 6, 2007)

Kilted said:
			
		

> Hogwildz said:
> 
> 
> 
> ...


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## elkimmeg (Jul 6, 2007)

I installed a mini split in the latest addition I did a 3 season room  the only exterior protrusion needed was a 2.5" hole saw cut needed to attach the feed and return lines and the low voltage electrical wire   bell wire gage the interior exchanger is run with  very effecient 24 volts To make it easier to install t installation kit is available where not cuts are needed in the cooling lines.
 one can shporten them up cut them to length using a flaring tool or leave the coil neatly tucked out of site To answer NY soapstone  questions the unit comes fully charged. the only special tool needed is the evac of the system before  turning it on. which the unit has screw on fittings for the EVac. The interior exchanger mounts on a  melta mounting  bracket that can be installed with the supplied screws or one can use longer drywall screws to have stud penetration threw the plaster  reminder to line the unit up to miss the studs with the 2.5" hole cut out ant to level the bracket instasllation.  I did form and pour a concrete slab for the mini compressor which is installed under the 3 season room out of site behind privacy lattice. The compressor did require  10/3 wire and a 30 amp service and a   30 amp bust fuze remote weather proof curcuit shut offf box It made sense to me to service the equipment to be able to shut it down remotely near the unit than to go back inside and flip the breakers pluss the added in line fuse protection Wiring was explained and straright forward One has to keep track of the low voltage wires but it was explained 
 the connon DIY should be able to figure it out common bell wire nuts were used to connect the unit exchanger withing the home..  So all systems are a go power is recorded and I fire the unit it goes on one second and beeps then nada. I read the manual then call customer support I give then my voltage readings and it is determined I have a faulty computer board After them sending 2 incorrect boards and me taking apart the exchanger housing I a bit pissed the boards do not interface with the plug ins on the unit Finally I am sent the correct board aND IT TOOK TAKING THE OLD ONE OUT AND SENDING IT TO THE SUPPLIER TO GET THE RIGHT ONE. This has taken a month and The homeowner is holding a considerable  final payment check. To maKE MATTERS WORSE  I was not charging for the installation. I figured what's an extra hour work when I made out ok on the job. Let me tell you it turned into a lot of extra time and agrevation.

With the b new board installed it has worked flawlessly. I q guess this can happen on any manufactures products we here about board failures dealing with pellet stoves.

 Ok real world expectations  the unit is far more effecient than window units and runs a lot quieter Not only does it satisfy the 33 season room but also takes care of the adjoining kitchen dining area. This mini split also can heat though they cannot completely carry the load below 30 degrees A backup electric baseboard system was installed.  Remember this is a 3 season room that with the backup can be used year round. The strong point of the system is its Ac capabilities. Did I mention it is remote controlled.

I( bought this Unit  over the internet and  I think the entire cost including installation kit was less than $1200 If one want more info I can take pictures of the installation and post them plus I will supply the internet site where I bought it. Sanyo is the leading brand name for these mini splits.  Mine was a reconized name but I can't remember it now but the compressor was made by Panasonic It might have been Fridigiare. Iknow (SP) again


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## senorFrog (Jul 7, 2007)

I bought a portable AC unit and returned it.  It was just so BIG in the room!  With the two vent hoses it reminded me of the robot from lost in space.  I do like the idea of just wheeling it in for the summer.  Window units are such a PITA and don't seem to get any lighter.

When researching the portables try to get one that evaporates the condensation out the exhaust instead of into a drip pan, which you'll have to empty every day.  Also, they are not as efficient as window units for a variety of reasons.

Hands down, the best window unit I've found is the Panasonic...

http://tinyurl.com/2l3vnq (Tiny edit by Mo, try it yourself at: http://tinyurl.com/)

It's very well made.  I can cool a 20x20 den and adjacent breakfast nook plus kitchen with this single unit!  I just use the same air circulation strategy that I do with my wood stove.

I did research the split unit Mitsubishi Mr Slims.  They are intriguing, but cost prohibitive right now.  I think they start around $3000 installed.


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## titan (Jul 7, 2007)

Check out "DAIKIN".....they make some nice ductless split heat pumps.They're using "inverters" in the condensing units;super quiet,efficient,rated to operate down to -18*C.


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## begreen (Jul 7, 2007)

Daikin is big in other countries but rare here in the US. I tried to find a Daikin sales office locally, but the closest was in CA. Too bad, they seem well proven in places like Australia. Are they popular in Canada?

Sanyo, Panasonic and Mitsubishi are making in roads into the American HVAC market, but the big ones here still are Trane/Amer. Std., Carrier/Bryant, GE and Goodman, none of which are using the advanced inverter technology in the Japanese units.


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## titan (Jul 7, 2007)

BG,Daikin has only come to the fore here in the last 8-9 months but I believe I read in a brochure that they were being shipped from a dist. centre in Texas?Anyways, I've worked on or installed most brand name units....I don't feel one is much different or better than another.....however this inverter tech. showing up in affordable,residential a/c units is notable.Time will tell if they hold up in our climate but if I were buying one for my own use,I'd lean towards Daikin right now.    FWIW-the 24000 btu heatpump I just installed had a SEER rating of 16 with its' R-410a refrigerant.


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## Hogwildz (Jul 26, 2007)

Gentlemen,
after receiving 3 quotes for central AC, I just cannot bring myself to spend 10k or more for central AC.
I am very interested in the ductless. 
Elk, I would greatly appreciate you installation photos & input. Central I would not consider doing myself. The mini splits I may contemplate.
Or maybe just have someone install. I just can't justify spending tons of cash I don't have to waste on an inefficient central system that will cool areas at times that do not need to be cooled. I have been thinking of maybe window unit, which in my case would be some casement units and a couple larger regular window units.
I know the cost would be cheaper, but I just don't want all that crap hanging out of windows and also the taking in and out each year factor.
I appreciate any input.


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## tradergordo (Jul 31, 2007)

Yea, thanks for the ideas everyone.  I too am looking to make a change.  I already have central AC but its an older, inefficient, Carrier model.  When its working it cools the house just fine, but lately it has been giving me problems (its in its 9th season now), it has been icing over (when this happens on the inside (evaporator coils? I don't really know much about AC repair) it blocks the flow of air, so the thing will run continuously without any airflow which is really not good (doesn't cool the house and probably overloads the fan).  Had to teach the wife that turning down the thermostat temp will not make the house cooler if the AC is not working  

At any rate - I've already taken this thing apart and cleaned it twice this season (outside and inside).  I don't feel like paying a few hundred to a repair guy at this point, I'd rather put the money towards something better.  So like many of you, I'm still in the research stage and don't quite know what to do yet.

Elk I would love to see the photos you mentioned and the link to the product you recommend.  I'm also interested in links to the other products mentioned here.  I'm sure I can get by with what I have for this year, but next year I'd like to try something different.  I would like a DIY install if possible.


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## Mo Heat (Jul 31, 2007)

tradergordo said:
			
		

> ...lately it has been giving me problems (its in its 9th season now), it has been icing over



I'm no expert, but when my A/C (18 yr old Lennox central unit) was acting up this spring I called up my father-in-law, a retired EE guy, and asked his help. His first question to me was, "Is it icing up?" I said no, but he said, "If it was, it is probably just low on freon". 

It did ice up the year before and was 4 lbs low. This last spring it didn't ice up, but it was only 2 lbs low on freon. It cost me about $175 both times to top off the freon. Might be worth that much just to see if it fixes the problem.


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## elkimmeg (Jul 31, 2007)

Mo mentioned the coolant problem but there is another one lack of returns will ice up systems  I don't know what it is but it seems all Contractors have enought supplys but have a brain fart concerning returns Ac the returns should be located high in the rooms That one central in the upstairs hall  is next to useless never moves air in the bedrooms Again a very ineffecient way.
 I will never pass a system where supply =returns and if a door can be closed then I consider it closed all the time and a separate return required..

Again more emphasis is give to heat distrobution than AC  Did you know Ac requires larger ducting than Heating yet for years combined systems sacrifice both task accomplishing neither effeciently or effectively... Let me ask a question have you increased insulation in the attic.. Improved windows? ( years old you should not be having these problems in designed and installed correctly..  Well do you have cheap ass builder special equipment? Before more money is thrown away and another idiot  recharges a charged system lets figure out what you have and how it improve it I need some more info Trader I willing to bet with guidence you can make the improvements


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## elkimmeg (Jul 31, 2007)

Mo instead of charging a system every year itime to figure out where the leakage is


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## GVA (Aug 1, 2007)

Also important to note here that the compressor will run 30 some odd degrees lower than the thermostat setpoint, (And no it doesn't get the room cooler quicker the lower you set it)
so someone set's it to 60* on a nice hot humid day and guess what forms?????
After years of climbing on the roof to thaw out the rooftop units I had My HVAC guy set up the units with some sort of switch so that no matter what the T-stat is set at the compresser will never drop below 36* (I think that's the temp)
anyway The only time I have a unit freeze up now is if the condenser fan has a belt that is slipping, or belt breaks.....


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## elkimmeg (Aug 1, 2007)

Gva brings up another good point. Common practice is oversizing the compressors,  which results in short cycling and freeze ups plus gross insffeciencys

 Couple in lack of adequate return systems and your have a formular that is doomed for failure


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## Mo Heat (Aug 1, 2007)

elkimmeg said:
			
		

> Mo instead of charging a system every year itime to figure out where the leakage is



That would seem to be the proper course of action, and in fact, that is what I asked the technician to do. Judging by his demeanor and reply (and I wasn't at all impressed with this guy like I was the one I got the year before from the same company), and all his hemming and hawing, I concluded he either didn't want to do it, didn't know how to do it, or would have taken a long time to do it. At $150 per hour, with a reluctant and possibly incompetent technician, and with absolute zero guarantee (hee, hee) of actually finding the leak, and being able to fix it, unless it was one of the connectors along the run and not inside the nearly 20 year old heat exchanger, I decided to cut my losses and go with his recommendation of pumping some more cold juice in there. 

This guy was so disorganized (and a real BS'er of the worst kind... he called me "Bud" about 40 times) that he'd left the shop without any cold juice. That added another two hours onto the service call and I believe he padded the bill with an extra $35 in labor (nothing else was done and no explanation) to get something for the two hours he was smoking cigarettes out front in his air conditioned truck while waiting for another truck to deliver the cold juice. He was going to leave after changing his story about needing just a little more freon after his nearly spent tank gave out and he discovered he only had two empties in the truck instead of two full tanks. If I hadn't been out there watching and asking questions, he'd have left just to avoid the delay and I'd have had about one pound added instead of two. Nice guy. At least he responded to some deliberate questioning and came clean. I half expected him to pull a BS rabbit out of his hat and leave anyway. 

So, in the end, I paid up, since it was the same price as the year before and I didn't feel like arguing with a stump.

Anyway, since topping up the unit worked last year, I figured it would work again this year, and it did: problem put off for one more year... as of now. When other people are involved, sometimes things don't go the way you want them to.

It's cool in here, but now my thermostat is on the blink. It keeps resetting itself to the default factory set-back program so I'm shopping for a new one.


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## tradergordo (Aug 4, 2007)

I think its probably the coolant problem in my case, sure sounds like it anway.  It did ice over once last year, but the first 7 years of its life were just fine.  I guess I just wish I had something more efficient that's all.  Yes, its a "builder special" Carrier model.  To give the builder credit though I'm pretty sure its properly sized for my house and there are plenty of return vents (large and placed at the tops of the rooms and hallways).

Anyone know if its possible to do a recharge yourself or to find leaks yourself?  This goes back again to not wanting to spend money on a system I think I should replace, then again, maybe spending $200 to fix what I have is better than spending a lot more to replace it.




			
				elkimmeg said:
			
		

> Mo mentioned the coolant problem but there is another one lack of returns will ice up systems  I don't know what it is but it seems all Contractors have enought supplys but have a brain fart concerning returns Ac the returns should be located high in the rooms That one central in the upstairs hall  is next to useless never moves air in the bedrooms Again a very ineffecient way.
> I will never pass a system where supply =returns and if a door can be closed then I consider it closed all the time and a separate return required..
> 
> Again more emphasis is give to heat distrobution than AC  Did you know Ac requires larger ducting than Heating yet for years combined systems sacrifice both task accomplishing neither effeciently or effectively... Let me ask a question have you increased insulation in the attic.. Improved windows? ( years old you should not be having these problems in designed and installed correctly..  Well do you have cheap ass builder special equipment? Before more money is thrown away and another idiot  recharges a charged system lets figure out what you have and how it improve it I need some more info Trader I willing to bet with guidence you can make the improvements


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## elkimmeg (Aug 4, 2007)

Trader there is a little more involved then just adding coolant after the system has been charged it has to be evaced usually accomplished using a vacume type connections and gages.

Yes 7 years residual coolant loss is common  enough to effect system preformance.  Time to get it recharged that small copper coolant line can hold up to 150 psi  better read up on how it is done before un doing that line Some suprises can be quite unpleasent


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## begreen (Aug 4, 2007)

> Anyone know if its possible to do a recharge yourself or to find leaks yourself?  This goes back again to not wanting to spend money on a system I think I should replace, then again, maybe spending $200 to fix what I have is better than spending a lot more to replace it.



No, not legally at least. Freon leakage is a major reason for the degradation of the ozone layer. There used to be incredible, careless waste in the refrigerant industry. It's now tightly regulated. When a system is worked on or purged, all evacuated freon is supposed to be captured and recycled. 

Best to have the system gone over with a halon gas leak detector. That you can do by yourself if you buy the tool. Then have the leak(s) fixed by a reliable mechanic and the system recharged. Given that this is happening to multiple core forum users, maybe you could all go in on the price of the tool and share it?

http://www.reliabilitydirectstore.c...838-Refrigerant-Leak-Detector-p/rdi-ar838.htm


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## tradergordo (Aug 6, 2007)

That's probably not a bad idea (sharing a detector) but I did a bunch of research and based on what I read, virtually all air conditioners leak - its just a matter of how fast.  A seven year leak it seems is not unusual, it would probably be impossible to detect even with expensive equipment being used by a trained technician.  Now if I recharged it and just as much had leaked out within 2 years, then it would be considered an unacceptable leak (this applies to car air conditioners as well from what I read).  I also see that it is illegal to do the recharge yourself (for central AC, but not for automobile) so I guess I don't have much choice in my case as far as a do-it-yourself solution.


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## begreen (Aug 6, 2007)

That's assuming that it leaked gradually over 7 years. It might have been fine for 5 years and leaked over just 2. I have a hard time buying into the notion that all systems leak. Automotive systems have more confounding factors (vibration, hoses instead of hard-plumbed) and can go 12 years or more without a leak. Refrigerators can go over 20 years and still work. My suspicion is that most A/C system leaks relate to the quality of installation. First suspect would be flare joints, then welds.


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## tradergordo (Aug 7, 2007)

For what its worth - I had the AC repair guy come out last night.  My central air unit was short about 3/4 lb. of coolant (which isn't a real big loss, but enough to cause problems).  The guy showed me another way to quickly test performance - the air coming out of the registers should be between 17 and 22 degrees cooler than the air going into the return vents.  At the time, the air going into the return vents was 83 degrees, and the air coming out the register was 72 degrees.  After adding the coolant it almost immediately went down to 68 degrees, and when I checked it later, it was down to 58 degrees (right around the optimal 22 degree difference).  We are having a heat wave in PA right now, high of 94 (that's hot for us) and the wife says the AC is working better than ever so I guess the $148 was worth it.

For what its worth, I also learned that a typical rule of thumb for sizing a central AC unit is about 1 ton per 600 square feet of area to cool.  At 3.5 tons, my unit is considerably undersized for my house (thanks a lot Mr. Home builder!).  Although to tell you the truth it performed quite well for its first 8 years and its doing fine right now after the coolant charge so maybe the builder didn't really screw it up...

One nice feature I see on a  lot of new homes today is a metal shelf permanently fixed to the foundation of the house that the outside air conditioner sits on - this prevents damage (leaks!) from shifting ground underneath the AC unit, I think its a very good idea, probably also helps a little to keep mold and critters (bugs, mice) from getting inside the unit especially in the off season.


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## Mo Heat (Aug 7, 2007)

tradergordo said:
			
		

> ... the wife says the AC is working better than ever so I guess the $148 was worth it.



Glad to hear it. I know the relief you must feel since I went through the same thing the last two years (I might actually benefit from finding my leak). Nothing like cool, dry air inside when it's sweltering outside.


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## BrotherBart (Aug 7, 2007)

On the charge it yourself front, I used to charge my own. I kept an eye over my shoulder since the last time I checked the max Fed fine for a Freon discharge to atmosphere was $250,000. Of course a friendly judge could cut it down to some easily managed figure like $50,000 or so.


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## Kilted (Aug 8, 2007)

Super Efficient Air Conditioner

Checkout http://www.coolerado.com/

Check out the videos page:
http://www.coolerado.com/CoolSchool/CoolSchool.htm

So I know nothing about this unit. A friend dropped this on me today.  Hopefully some one here knows a little about HVAC systems.

Since the working fluids here are air and water this is essentially a swamp cooler, with the difference that the swampy air stream is directed outside.

In one of the video's He is using a space heater to provide hot dry air as input this seems to make the demo unit work well.  There are charts showing what parts of the country this system works in.  It would seem to work in a hot dry climates.  It would work best in an attic vs outside.  The attic providing hotter air than ambient outside.  Another problem I see is volume of cooled air, because of restrictive airflow air delivery could be lower than required.

There is an evaluation by PG&E;you need to wade through some math.

--  Brandy


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## Sandor (Aug 8, 2007)

tradergordo said:
			
		

> so maybe the builder didn't really screw it up...



You should thank your builder. Oversized A/C units will cause many problems. The largest problem is that the unit does not run long enough to effectively de-humidify.

Everyone is way better off undersizing than oversizing.


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## begreen (Aug 8, 2007)

Kilted said:
			
		

> Super Efficient Air Conditioner
> 
> Checkout http://www.coolerado.com/
> 
> ...



This is not an air-conditioner but a sophisticated, indirect evaporative cooler. It would work ok in dry climates, but my guess is it would be sub-par in the humid heat folks are experiencing back east.

From the executive summary of PG&E;'s testing:
The advantage of an indirect evaporative cooler is that it accomplishes low-cost evaporative cooling
without adding any moisture to the air supplied to the conditioned space. However, the high flow
resistance of the heat and mass exchange modules in this unit resulted in significantly lower supplied
airflow and higher power consumption relative to typical direct evaporative coolers.

In other words, it doesn't work as well as a direct evaporative cooler, but does have the advantage of not adding humidity to the air that is typical with direct evap (swamp) coolers.


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