A/c window unit storage

You should always store them flat.

If they must be stored unlfat, it's best to store them on their back, with the outside face down. Be careful nothing is under it to distort the fins though.

I've done it for years - haven't had a failure yet, period, of any ac I had with the exception of a 1983 model finally corroded thru the pipe in the back side when I tried to wash out the debris with a hose. I don't use a hose full force anymore .

Side storage can cause the oil to run out of the compressor. In many cases, leaving it sit flat will be OK, but it is also possible to do permanent damage. This is discussed here frequently about moving refrigerators laying down. Search on the google groups will find results. Same answers apply.

With some models, the oil will migrate out of the compressor.

Not recommended as the oil could drain into the cap tube and cause a restriction.

First, the pressure is equalized in about 5 minutes on any model.

If the compressor is a piston type, turning it on its side is signing its death warrant.

Thanks guys, its in flat position now, and since it's only a few years old, I'm going to sell it on ebay. chas