Can I install window air conditioner in reverse position

[Chris]

Hello,

I would need to install my existing window AC on my new house in one room. I do not plan to buy another AC this year.

My question is: could I install the AC on the lead of the attic access, with the face down. In that way the ~exterior~ would be the attic and the AC would push down the cold flow air. The lead for access to the attic is on the wardrobe, which is next to my bedroom where I need the AC.

I can not install it on the existing windows, different model and size.

Thank you, Chris

[Joseph Meehan]

That would give you two serious problems.

First the condensation would drip out onto the floor. Second you would find it very inefficient since it would be pumping heat into the already very hot attic, making the attic even hotter and not providing as much cool air below. With the attic hotter even more heat would come through the ceiling. Finally those units are not designed to stand up on end so we don't know if it might damage the unit running that way.

Sell what you have in a yard sell and buy a new (likely more efficient) unit at the store, one that will fit the new window.

[John Grabowski]

It probably will not cool too well as it needs to dissipate heat and use fresh air to cool. If there is an attic fan to bring in air into the attic you may get some cooling. As Ken pointed out you will probably have a problem with condensation. I seem to recall that there are air conditioners that sling the condensation onto the coil. If yours is one of them it will not function correctly.

[trader4]

Sounds like a bad idea. The condensation has to go somewhere and mounted facing down, that's going to be dripping down out of the front. I'd also have doubts as to whether the compressor was designed to run rotated 90 deg from normal and would function normally without damage, etc.

[Ken]

Have you given any thought to what path the condensation would take if mounted in an incorrect manner? Does not sound like a good idea to me.

[ransley]

No you will ruin the compressor it wont lubricate, it will likely break loose and the condensation will enter the house

[trader4]

Can always count on Nick to come up with something practical. You think wetting the basement floor with a soaker hose to cool an upstairs room is sound advice? Ever hear of mold, condensation on cold pipes, wood rot, rust, etc?

[nicksanspam]

No, but you might install it in the usual way through a wall into a stairwell that's open to the attic. In wintertime, close the attic door and sprinkle water on the basement floor with a soaker hose and a solenoid valve and a 60% humidistat and rotate the AC 180 degrees to warm the room like a heat pump with a 3:1 COP :-)

Nick

[S. Barker]

It probably wouldn't work, as the 110-140 degree air in the attic would not cool the condenser sufficiently. Also, what about the drip?

s

[Dave Martindale]

A window AC unit will only work properly when installed as designed. This generally means with the bottom almost horizontal, actually tilted a few degrees towards the outside. That's because gravity has a large influence on the flow of liquids, and there are three liquids involved that would be affected by any other orientation:

1. Water. Water condenses on the evaporator, where it's supposed to be collected by a pan under the evaporator in the "indoor" portion, then run to the "outdoor" side of the unit (that's what the few degrees of tilt is for). Once in the outdoor side, it's often splashed onto the condenser by the fan. This cools the condenser, and makes the unit more efficient. And if there is too much water for the unit to handle, it drips off the outside of the unit.

If you mount the unit face down, the condensate will drip back into your room.

1. Refrigerant The refrigerant turns from gas into liquid in the condenser. Once liquid, it flows to the bottom of the condenser where the liquid is then fed through the capillary tube and on to the evaporator. If the unit is mounted face down, the liquid refrigerant will likely pool somewhere other than the intended "bottom" of the condenser.
2. Oil The sealed compressor housing includes some oil that lubricates the compressor bearings, piston rings, valves, etc. If you mount the unit face down, the reservoir of oil inside the compressor will move to somewhere it's not supposed to be. You could get poor lubrication, or too much oil in the cylinder during compression. You might destroy the compressor in short order.

Sell the existing one, buy new one that will fit.

Dave

[nicksanspam]

To WARM the room, nitwit :-)

Sure. Happens over 60% RH.

Nick

[Stormin Mormon]

Window AC have a "right side up" for compressor lube oil, and a bunch of other reasons. That said, you could duct the cold air with metal or other material. If the attic gets rather hot, then the AC won't work properly. You'll need attic venting, also.

[Edwin Pawlowski]

Sure can. Let me know when you do and I'll get a six-pack and we can drink and watch the redneck entertainment when you turn it on.

[georgesweeney]

Your answer is NO. Others have already explained why.

But if you planned to go thru the trouble of cutting a hole in the ceiling, just cut a hole in the wall about 2/3 the height from the floor. Cut between the studs, thru the siding. You'll probably have to cut out one stud. Put a piece of 2x4 across the top and bottom of the cut out hole to reinforce the cut stud. Add trim on inside and outside and install the AC. This is done quite a bit in office buildings, and it dont waste a window.

[Stormin Mormon]

He's late for dinner. Again.