proper A/C window unit installation

[rdavy]

About three years ago I installed a window unit in our living room as the central A/C unit just wasn't sufficiently cooling the living room when the outdoor temp went over 100F. Last year we had an exceptionally wet year and we got a wet spot on the window frame, sheet rock and floor below the unit. The rains stopped and I had almost forgotten about it since we are now in a severe drought (1.25 inch rainfall since Jan 01). LAst night we had a heavy thunderstorm and within ten minutes I noticed the window area getting wet.

For insulation value and a little more security I had installed a piece of 1/2" plywood around the exterior of the window unit. Then I filled the space between the plastic curtains on the unit and the plywood with canned foam.

I don't guess this was the best idea one could have. I'm now thinking of loosening the plywood from the foam and removing foam and plywood. What is the proper way to install a window unit?

PS -Purchased your manual a few weeks back. Wish I would have done so before moving in here.

[Robert]

Hi,

The BEST way is through the wall and as high as possible within safe reach for controls and/or needed repair/cleaning.


This is also the safest against break-ins and theft.


Through the window, unless it is an upgraded window, will usually give rattles, leaks, easy entrance/theft if not really modified well.


Through the window, the plastic sides deteriorate, you can't use treated plywood and regular plywood rots from wetness.


Through the wall gets a tight fit, seal the seams and all is good.


Thanks for inquiring,
Robert

[Robert]

Going to move this to the Heating & Cooling Forums (All Other HVAC Questions).


Please follow it there .


Thanks,
Robert

[rdavy]

Thanks for the advice. Think I might change windows, first build a frame to mount the AC unit in and the rest of the opening window.

I've put lots of them in stick built houses with no problems but these MHs have no overhang and the window is right in the weather!

[Robert]

Yep and don't forget that if regular aluminum window, it if flimsy and doesn't hold up to the vibration.


Just remember that you'll have to use untreated wood and if it gets wet often enough, it will rot.



Take care and best wishes,
Robert

[oldfart]

Well fellers...been there done that! My first tip is install a new double-hung window properly framed and sealed and then install the A/C unit just like the manufacturer suggests. On the outside it wouldn't hurt to pick up some angle-alum. to build a brace to help support the underside of the A/C unit. Some of them puppies are heavy! Save the box and come fall take the unit out and clean it before re-packing it and storing. Now..about installing one thru the wall...hmmm? I have some problems with that. First off, the wall-studs on older mobile homes warn't designed to support the weight. (same problem as with the windows..) Eventually the walls and paneling bows out at the top and in at the bottom. An you got leaks. My second warning is, sooner or later you're gonn'a have to replace that A/C unit and what chance do ya think yer gonn'a find one anywhere close to the same size as the old one? Every year they're making things smaller...A/C units too. Making the hole bigger is easy..makin' it smaller ain't so easy! For the price of 1 properly installed window ya save all this hassle. Finally..stop plugging them units into the same circuit your 'fridge/micro-wave and sundry other things are plugged into. Even the single-room units should have a dedicated circuit just for that A/C unit. Audie..the rambeling Oldfart..

[Robert]

I have yet to have ANY problems from installing a through the wall window unit in 29 years in HVAC service.


I can do it as fast as replacing the window and alot cheaper. The studs and any problems can be taken care of.


A properly cared for unit will last a very long time and any size changes can be taken care of as well.


You also won't have the stress of then wanting all windows to match and having to replace others before you're ready.


You get the unit up higher also where it works better and lessens chances of theft.


Both ways can work and homeowner can choose best for them at time, but don't be so quick to discard a proven method.


I've been there and done that too, many times and it has withstood the tests of time without fail yet.


Take care and best wishes,
Robert