Am I missing something about window A/C?

Warning - this post contains redneck engineering.

We’ve moved into a new apartment, and it is such that we can’t use our window A/C unit. It is also sweltering hot at the moment, so I used a little improvisation:

The entire unit is outside on the balcony, and the cold air outlet is spoojed to a length of ducting that leads to a vent in the wall. There is a definite improvement, but it’s not nearly as cool as it was in the old place. (Where it was installed in the more usual fashion.) I’m wondering if I’ve missed something, or if there are other variables at work.

The model is more-or-less like this. I jerry-rigged an adapter from the topmost vents - technically, the bit what’s got the cold air blowing out it.

What’s giving me pause is the bottom three quarters of the unit, which has the appearance of a grill, sorta. More puzzlingly (to me) it’s equipped with a dust filter, as through it is intended to have air blowing through it. (If any air blows through there, I sure can’t feel it.)

So, Dopers - is there any reason that putting the entire condensing unit outside and ducting the cold air inside would not work as well as having the thing sitting in a window?

What is the purpose of that air filter, anyway?

Window A/Cs are designed to suck in room air through the lower vent grille and cool it. The filter keeps dust away from the evaporator coils. Your setup always draws in warm outside air. In a normal setup the cooled air is recirculated through the unit.

Dude, really?

That big section with the air filter is sucking the air from the room, running it over the cooling coils, and blowing it out, freezing cold, back into the room. The filter is there to protect the innards from all the crap that’s being sucked in (pet hair, dust, people hair, whatever’s floating around the house).

Efficiency and overall cooling are achieved from the a/c being able to continually cool off the same load of air, in turn getting it cooler and cooler until it’s at the temperature you’ve set. If the unit is outside, sucking in the hot air constantly, it will run constantly instead of cycling on and off like it should, and it won’t be able to cool the load of air that’s inside the house.

You will kill the air conditioner sooner than later, and you will have one hell of an electric bill.

Ha! Brilliant.

One more duct, I guess. :smack:

**sheepishly hums the theme from Brazil **

…this is only my second-stupidest GQ, too.

You’ve already got your answer, but I’d like to clarify this point. There is no problem with having the entire condensing unit outside. That’s where it’s supposed to be. But the evaporating portion needs to be inside.

The evaporator are the coils behind the filter that absorb heat, the condenser is the set of coils on the back the dump the heat to the outside world. As SeaDragon mentioned having the evaporator outside means that instead of the AC trying to bring 80 degree air down to 70, it’s trying to bring 100 degree air down to 70. It’s all about the Delta T.

A second duct will should help considerably.

Can you clarify what you mean by having a piece of duct running to a vent in the wall? Are you trying to connect the duct to existing central duct work in an attempt to distribute the cold air throughout the house? If that’s what you’re doing I don’t think it’ll work. The blower in a window AC isn’t going to move enough air to do that. You’d be better off just running the duct into the house and then using room fans to move the cold air from room to room.


Talk about Fighting Ignorance…

This was impressive to me. The poor guy was truly ignorant…definably ignorant…and that ignorance was beaten off him like a raccoon off a trash can. Wait…bad analogy…

Anyway - glad to see you get it now. Be careful who you share this newfound knowledge with - they may be a little rude.

Cite for the first? :stuck_out_tongue:

Oh, I think Larry took the information in the jesty way it was intended. It was more surprise on my part, because he’s such a smart guy - and he knows it!

I’m just really curious about the windows. Are they casements, that can’t “close down” on top of the window a/c and won’t hold it in? If it helps at all, the way my a/c’s are installed, they’re done so the window can still be opened a bit above them - a piece of 1x2 wood was fitted into the window track so it would wedge in tight, and that’s what’s holding the appliance in - instead of the bottom of the window frame, so the window is still free to move without dumping the a/c out and down 3 stories.

If you have casements, you could do something similar, and then either cut a piece of plywood or plexiglass (depending on whether you care to see out) to fit the remainder, and just caulk it into place for the rest of the season.

[quote=“Joey_P, post:6, topic:550487”]

It’s just a pass-through vent, and although the area is a little larger than the unit is appropriate for, it’ll still do.

Nah, the windows are multipanel, and the panels that open are directly above nothin’ but glass.

For years I added salt to water for pasta, and often thought of my older brother explaining that it increased the boiling point of the water and thus helped with the cooking process. Eventually it dawned on me that the amount of salt you’d typically add to water for pasta could not possibly affect the boiling point in any significant way… so I wondered… why do we put salt in water for pasta? A real mystery, that one.

Now, back to my International Space Station improvisational project. I am a bit bummed to have turned the damn thing off - moronic or not, it did make the place habitable, even as it was. (With god as my witness, I thought turk-- I mean, I thought window units drew from the outside… and on some level I knew that it weren’t so when I sussed the air filter, but I really didn’t want to go back to the Home Depot and cough up another $5.99.)

Don’t forget the worst thing about single-ducting in only the cold air… An A/C unit not only cools the temperature, but lowers humidity, which is often more significant. By not actually recirculating the air of the rooms interior, you aren’t doing anything for the humidity.


Ooooh, ooooh, pick me! Pick me! (Finally a GQ I can answer!)
You salt the water because the pasta absorbs the water, therefore, it absorbs the flavoring power of the salt, too. It’s your best opportunity to enhance the flavor of the pasta itself, as opposed to dumping a bunch of wonderful sauce on pasta that tastes like chewy, starchy. . .nothingness.

Is buying a room A/C unit out of the question? It will do what you want much more effectively.

Your answer is (of course,) technically correct, but you can really underscore the stupidity of the question by being more concise, thus: “To make the pasta salty, idjit.”

There isn’t really room in the budget to justify it. Will probably get a portable unit for next summer, but I’m pleased if a <$20 expenditure will get us through the next couple of hot, sticky weeks - before the return to Vancouver’s Rainy Season. (September 1st to June 16th.)

The alternate response you suggest, was, of course, my first choice for a response. But this is GQ, after all, so I’m not technically allowed to call you an “idjit”, which could be construed as a personal insult. :wink:

Okay, we’re on to pasta now, but It’s probably also worth mentioning that unless the intake draws interior air, you’re increasing the pressure inside the apartment. Since your apartment isn’t airtight, in addition to making the unit work harder to pump that air, it’s also going to push the already poorly cooled interior air right back outside.

Which means it gets clammy inside because as the temperature decreases the relative humidity increases.

Well, I ducted the intake so it’s drawing from inside, and darned if that doesn’t make a dramatic difference. Of course, the whole business looks comically like an early Dr. Who prop, but the breathable atmosphere makes up for that a bit.

When I unpack my camera, I have a ready entry for

I was going to suggest you post your kludge but I see you’ve already planned to do that.

Also, I can definitely recommend a portable a/c unit, it’s what’s keeping me and my pets alive this summer. The higher electric bills aren’t fun, but it’s better than melting into a puddle of goo.