Hot town, summer in the city...

August 28, 2011 3:29 PM

It is hot in LA, and we were just gifted with a window-unit air conditioner! Hurrah! We have bars on all our windows! Boo! We've rigged up a very rickety looking system and it works, but...I feel like we might be setting ourselves up for disaster?

Standard sized in-window air conditioning unit. We've propped it up on the inside of our living room window part of it resting on the windowsill, part of it on table, to where it is still inside the window - meaning, inside both the window screen and the bars. Furthermore, there's a good several inches on either side of the unit, as the window is wider than the unit. We turned it on, and well - it is certainly working.

But! This is obviously not ideal. First off, I realize that by not creating a seal and the window being larger than the unit, it is wasteful. Any tips on figuring that out? I know that some units come with little expandable thingies on either side, but this one did not. Second - is there a problem with the unit being on the inside of the screen? I know traditionally, I see units fully outside the window like this. Third - will the unit create any condensation issues I should be aware of? Fourth - we have drapes. Do we need to keep the drapes very far away from the unit?

Important details: I'm on the first floor. I'm a renter. All utilities are included in my rent. We don't plan on running it very often except for August and September - traditionally the hottest months of the year. I've never had a home with an air conditioner before (recently moved to East LA from the cooler coastal area) and feel like a total n00b. Thanks!

posted by fillsthepews to home & garden (6 answers total)

Basically, whatever you do yourself to seal the inside bit of the A/C off from the outside bit of the A/C is going to be breathtakingly ugly, even without the bars. Technically you could use a few bits of blue tarp, duct-taped to the window frame and the shell of the A/C, to create a shitty "seal", but I have a lot of faith in people coming up with ways to make a couple of bucks and I have to believe that someone has invented something, either a material or a method, that will do this thing for you. I would go to a hardware store and speak to a hardware store person and see if you can brainstorm some solutions.

Are the bars cheaply-installed bars that you can unscrew/unbolt from the inside? Maybe you could do that. It would make it easier to put the A/C in. Anyway, just get the outside bit of the unit as close to the outside as you can, and jam the area surrounding it full of old towels and childhood toys. There will be a little spout thing on the outside bit, probably. That's where the water comes out of, so you might want to run a length of garden hose from it to make sure it doesn't get all through the house. If there's no garden bed outside you'll need to put a bucket down there and hope that nobody walks past and goes "Hey! Nice bucket! Just what I need!"

Strictly technically speaking though, you could just have the A/C unit sitting on a desk near the window and it will still create lovely cool air. It will just drip water everywhere and cost you a million dollars to run.
posted by tumid dahlia at 4:11 PM on August 28, 2011

I think they're supposed to tilt back/down out of the window slightly so that condensation drips out. The black dot in the back of the picture you linked may actually be a drain. If yours has an actual drain and you're willing to go to crazy backwoods jury-rigging territory, I guess you could get some sort of thin pan, like a length of Hot Wheels track sealed with putty under the unit, to go under the drain and extend the runoff path through the bars. Sashes made from cardboard and duct tape ought to look just about right next to that.
posted by Monsieur Caution at 4:15 PM on August 28, 2011

Air conditioners don't make cold air, they remove heat from the air. They do this, funny enough, by creating even MORE heat. All that heat hopefully goes out the back of the unit. If you put an air conditioner in the middle of a closed room it might be cool in front of the unit, but (rather quickly I imagine) the average temperature of the room will get hotter and hotter till the unit can't cool anymore.

So you have a couple problems here. The unit is split in two: the front part that circulates air from the room, and the back bart that hangs out the window and circulates air from the outside. There may be vents on the side of your unit, but if they're on the outside part then they need to be outside. Otherwise you're just sucking air from the room and pushing it outside and that won't make you cooler.

The other thing is air from the outside coming in through the window. You don't want that for obvious reasons.

Also, part of the way that air conditioners work is by removing humidity (water vapor) from the air. Dry air feels cooler to us because it helps our natural cooling system (sweat) be more effective. But that water vapor has to go somewhere, and again it's out the back of the unit as water. Underneath, in one of the back corners, there should be a hole in the pan for water to drip out. You'll also want that outside the window, or some system to make sure the water exits outside (consequences of not doing this: mold, wood rot, damaged walls, etc).

To help with the drainage hole, almost every window air conditioner is meant to be tilted, towards the back hole. So properly installed the back of the unit should be about half to a full inch lower than the front.

Finally, the compressor part of the unit isn't meant to run constantly. This might be hard for you to tell, but there's a fan that runs all the time (what pushes the air) and a compressor that runs less, maybe 50% of the time (what removes the heat). There is a sound difference if you know what you're looking for... the sound kind of gets deeper and it sounds like work.

The point is that if the unit has to struggle to much to remove heat from the air, and the compressor runs too often, you'll shorten the life of the unit. Proper seal around the window, proper tilt, proper installation all help the compressor do its job. It's free, so maybe you don't care, but there it is.
posted by sbutler at 4:33 PM on August 28, 2011 [2 favorites]

Damn, thanks guys. This is exactly the info I needed. I'm on the hunt for the method of drainage. so far, it just appears that the water just drips out from the back of the unit with no sort of way to channel it, which is troubling. Our current janky set up certainly is cooling the apartment, but you've all validated my fears about waste and drainage.
posted by fillsthepews at 4:38 PM on August 28, 2011

There are security bars that are designed to accommodate window a/c units (though I can't immediately find any examples online right now). It's probably a long shot, but you might check with your landlord to see if there's any chance they'd install new ones for you.
posted by scody at 4:50 PM on August 28, 2011

What size is it? Can you set it on top of something wire/mesh that will allow the water to drain down, and put a drain pan below it? Pointing a fan toward the back-end of the unit and the window might also help channel some of the hot exhaust air back out the window.
posted by booknerd at 8:47 AM on August 29, 2011