Ask MetaFilter questions tagged with airconditioning

Will closing all but one vent in an apartment with central air cause leaks in the duct work?

weakcore — Fri, 17 Jul 2009 15:38:35 -0800

Will closing all but one vent in an apartment with central air cause leaks in the duct work (I mean, there are flaps on the vents for a reason, right?)? I rent a four room apartment with central air (South Eastern United States about 40 minutes South of the Appalachians). I really only care about keeping my computer room cold, which is the smallest of all four rooms (the others being the bedroom, living room, and kitchen) and also is where the thermostat is located.

I'm thinking about sealing all the vents in my apartment with the exception of the one vent in my computer room to save on cooling costs, because I can tolerate the other rooms being 85 deg. Fahrenheit, but not my poor computer (and seal of the computer room itself with some thick blankets suspended from curtain rods). It has occurred to me, however, that doing so could increase the pressure in the ducts and perhaps cause a leak, since the conditioned air from the central unit now only has one vent to escape from.

I have considered buying a single room air conditioner (and have also read the other ask mefi threads about single room air conditioning options). It seems to me that window units are much more efficient than portable units, but they pose somewhat of a security risk (my apartment being at ground level), and I don't know that my landlord would be so happy about my doing so.

Is there a way I can figure out what my the rating of my ducts is? Can anybody suggest other low cost solutions to bring the ambient temperature of my computer room down (Googling doesn't really present many solutions, although my Google-fu may also be a bit inadequate)?
Is my only recourse a window-mounted unit? Are there ways to address the security risk this presents?

Will American Home Shield replace my AC? Any good home warranty companies?

roaring beast — Mon, 13 Jul 2009 11:23:25 -0800

Can I expect American Home Shield or any other home warranty company to replace my A/C when it dies? Are there any other good, reliable home warranty companies out there? My current contract with AHS is about to run out. I have a 25+ year old A/C unit that probably doesn't have much time left. I also have a 12 year old water heater. After reading many reviews like these I am wondering if AHS will actually pay for a new unit. The warranty is supposed to cover these items, but it seems like most people either get excuses or are blamed for poor maintenance. Have you ever actually gotten a unit like this replaced? Should I renew my contract?

It looks like pretty much all the other reviews for home warranties are just as bad. Are there any home warranty companies that are actually good?

water mist to improve AC function?

BrooksCooper — Sat, 04 Jul 2009 11:55:24 -0800

Misting the AC compressor to increase efficiency? So, my home happens to have central AC - a rarity here in the US Pacific Northwest. There are usually only a week or two of days hot enough to use it every year. We are in one of those weeks now. I understand how AC works and understand how swamp coolers work.

I was wondering about combining the best of both to increase the efficiency of my central AC - My thought was to mist cool water onto the radiator fins of the compressor so that cool water absorbs heat and draws it away through evaporation. This would undoubtedly draw away more heat than just the convection / conduction through air contact with which the machine was designed.

Setting aside the minor complexity of building a mister with mist heads around the radiator which is triggered by the AC power flowing to the fan does anyone know if this would be a BAD idea?
Seems to me that if it makes AC cool better and thus cool the house faster then someone in the industry would already have marketed this as an add-on or upgrade if it was really useful.

This leads me to surmise that either the benefits are negligible OR the constant wetness / evaporation / deposit of minerals from the evaporated water is a problem over time.

Haven't experimented yet, other than just spraying the yard hose on the compressor and noting the dramatically greater subjective experience of heat exchange from it.

I'm just wondering if anyone has data on this question that would save me the time and expense of experimenting and collecting the data myself.

Does attic ventilation = more efficient air conditioning?

JFitzpatrick — Mon, 22 Jun 2009 08:50:15 -0800

Is leaving the windows in my attic cracked beneficial for keeping my air conditioning bill low? I'm curious if my present strategy has any benefit at all or if I'm misguided in my approach:

My home was built in the 1930s. The attic is half finished, half storage with windows on both ends of the space. There are no heating and cooling vents in the attic.

The door to the attic has weather stripping and a sturdy draft guard at the bottom.

During the summer the attic gets roastingly hot. It's better now that I installed a ridge vent instead of the cruddy little can vents, but it's still quite hot up there.

I've been opening the windows on each end to get a cross breeze which lowers the attic temp. easily 10-15 degrees. For what it's worth I live in a very windy area and there is a steady cross breeze almost 24/7.

Assuming that my floors and walls are properly insulated (the floor between the attic and the living space and the walls under the attic), which I believe they are based on my inspection... is leaving the windows open to provide natural ventilation (no powered fans that would create a negative pressure space) benefiting or hurting my energy efficiency with the air conditioner on?

It seems that lowering the attic temperature can only benefit me, but I'm not heating and cooling specialist and may be overlooking something outside my scope of knowledge.

Thanks!

Help me insulate my air conditioner!

kmtiszen — Tue, 27 Jan 2009 10:17:38 -0800

lI have a through-the-wal air conditioning unit. How do I stop the cold air outside from coming in through the cracks? I have a Friedrich WallMaster through-the-wall air conditioner that's great during the summer, but leaves my apartment exposed to the elements during the winter months. It's one of those sleeve models, so the back is just a grate that lets the cold air flow in with only the structure of the AC to stop it. The unit came with this foam wadding to help seal the edges, but it just doesn't do the trick. Is there some other insulating practice that I just don't know about?

THANKS!

Help me design a tall skinny flat window box fan

Aquaman — Thu, 02 Oct 2008 14:50:56 -0800

Help me design a tall skinny flat window box fan! I've got an idea for a box fan that consists of about a half dozen small PC-type fan enclosures mounted into a tall (3'-4' high), skinny (4" wide), flat (thickness of the fan enclosures) window box.

This insert would go into a side-sliding Milgard window, opened to the security stop (about 4" to the left). I'd like to put an in-line switch on the wire, and run it to a nearby outlet.

Here's where I need help: any suggestions for make and model of fan? And how can I wire these all together to run off of a standard 110v AC outlet? Thanks for your advice!

Need a new AC company

Ikazuchi — Thu, 18 Sep 2008 05:50:04 -0800

Does anyone know a good residential AC company in Tampa, FL? The company I have been using (Atlas Air) has been out 3 times in 6 months, and with my AC out again (this time for two weeks while we try to fix it ourselves), I'd like to try someone else before calling Atlas out again.

In or out? This sucks, that blows

Spyder's Game — Tue, 15 Jul 2008 11:11:30 -0800

Regular Floor Fan Filter: My wife swears that it's best to use a fan to "suck the hot air out of the room" first before turning the fan around to draw in the cooler evening air. I say the only hot air in the room is...well, help us figure this out! We have a very hot second story loft that never cools off from the air conditioning that cools the first floor so nicely. We keep the shades and windows closed during the day, and at night (as the outside world starts to cool off) I've been putting a fan in front of the screen door to our roof patio, hoping to draw in the cooler evening air into that hot room.

On more than one occasion, I've gone up there to see the fan facing TOWARDS the door blowing air (supposedly) out of the screen door. My wife's logic is that she's blowing the hot air out of the room, then will reverse the fan later, and draw the cooler night air into the room. This seems silly to me, and I promised I'd poll the hive mind to see if one or the other of us is "more right."

My logic is that if the floor fan faces OUT (blowing the air inside the room OUTSIDE), then you are taking the coolest air in the room (the air from the floor - which, let's be honest, isn't very cool, but at least cooler than the air eight feet above it) and blowing it out the door.

The fan is not huge, but it should be able to pull (or push) a little air around. Any thoughts? Who has it right?

Purchasing/installing mini-split ductless AC units in my house

ericbop — Mon, 14 Jul 2008 09:11:11 -0800

The previous question about mini-splits (one type of "ductless" AC) on askMe dealt only with complications of apartment dwellers. So, as a more general question, does anyone have advice on picking a good mini-split unit, and a reliable installer? I know that Mitsubishi is a big player for this type of item, but are they still as evil (environmentally) as they were last time I checked, in the '80's?

What would happen if I used a portable air conditioner in my car?

Toto_tot — Mon, 14 Jul 2008 08:23:51 -0800

Is this possible? Or just dumb? What would happen if we used one of those new, small, portable air-conditioners in a car on a temporary basis? We are from Canada heading through the Nevada desert in a small car and I am seriously wondering if it is possible to use one of those new portable air conditioners to keep us cool. We could run it off of the cigarette lighter and strap it into the back seat.
I have looked into those boat and trailer types that run a fan over ice and they get terrible reviews.
I don't have any experience with AC - we don't have it in our home either. (When it gets hot in the summer we suffer/cope and sleep in the basement)- so I don't know how it works. They seem to have to vent outside for some reason... I can see that...

What do you think?

Help with hot summer nights.

carsonb — Thu, 03 Jul 2008 16:17:07 -0800

Why is my bedroom consistently 10 degrees warmer than the rest of the house, and what can I do to cool it off? Here's a rough diagram of my apartment's layout. There are 4 vents for the AC, and the one intake is in the ceiling of the living room. I have vertical blinds on my south-facing window that I keep closed all day, and an oscillating fan that blows into my room from near the door. Trees block the morning sun onto my window, but noon to sundown I get direct sunlight. The vent in my room blows cold, and is not blocked at all as far as I can tell. The problem persists throughout the night. What can I do?

Why does my car A/C only work around town but not on the highway?

wheat — Fri, 13 Jun 2008 05:58:31 -0800

The A/C on my car ('92 Honda Prelude) works great from 0-40 mph. Above 40 mph, the ratio of cool to hot air moves decidedly in favor of hot. Any ideas (besides the obvious: take it to the shop).

Air conditioning broken, how do I complain?

Anonymous — Thu, 12 Jun 2008 14:11:36 -0800

Air conditioning has been broken in my apartment for 5 days now, what action should I take? I'm paying approximately 1500 a month in rent, and it has been above 90 degree temperatures outside during the past 5 days. I'm on a really high floor meaning it has to be like 10 degrees hotter inside my apartment than it is outside. I have three fans going and they're doing very little to help. It's so hot it's been very hard to even get to sleep.

Rumor has it they are offering a 50 dollar credit to compensate us. Do I take the credit and leave it all alone, or do I pursue some further action? If so, what should I ask for? (The air conditioning is still broken and we are currently on day 5.)

Does a shallow air conditioner exist?

logovisual — Tue, 10 Jun 2008 07:49:00 -0800

Can anybody suggest an extremely shallow in-window air conditioner, that I could possibly install in a window that has bars across it just a couple inches outside the screen? And don't waste your time suggesting a portable unit, as I'll describe inside. I'm DQing a portable unit because I just got one this weekend, and frankly, whatever gets suggested here would replace it because it just plain doesn't work. My room is only 140 sq ft and it barely drops the temperature by more than four degrees. Plus it fills up with water every three hours and has to be emptied. It's completely untenable.

In any event, I'm not sure the perfect unit exists, since only about three inches of the bulk could stick out the window, and in my experience most A/Cs need much more projection than that to vent properly. But maybe somebody knows of something I don't? I've seen past AskMeFi questions in which people claim to be running their A/C units almost completely inside the window; does anybody have any specific tips on how to make that work?

All around, people looking half dead/Walking on the sidewalk, hotter than a match head

SassHat — Mon, 09 Jun 2008 18:40:35 -0800

Yet another air conditioner question...please hope me. So I buckled today and bought a window air conditioner after a week straight of near-sleepless nights in my second floor apartment. Bought a 5000 BTU window unit, the kind meant for a window to shut down on top of it. My neighbor (in my building) has the same windows, same window a/c unit, and said it didn't cause him any problems. So I lugged the stupid thing home, nearly got heat stroke installing it, then hit a brick wall. Well two.

The first (and most important) thing is that the outlet nearest the two windows which would fit it (incidentally, in the kitchen) does not seem to have sufficient power to make it work. To test it, I set it on the edge of the counter and stretched the plug across to the outlet the fridge is plugged into...worked. This was fine to make sure the unit itself worked but there is no way the cord will reach that far, and if it did it would span the length of my kitchen.

So now I'm stuck with a unit that I can't power. I live in a bachelor apt and vaguely remember my landlord explaining to me that there wasn't an oven because there wasn't an outlet to plug it into and that she was going to have an electrician in some day (this was last sept). So now what? I put in a peeved voicemail with the landlady, she will likely take her sweet time on this, to the tune of me getting air conditioning some time next fall. My neighbor suggested an extension cord but that seems like a sketchy proposition at best. I've read the previous air conditioning askmes, but they were mostly about playing with wiring (something I will not and am not allowed to do). Any other workarounds you can suggest?

Secondly, should I ever get the power source issue taken care of - the window is a slide-sideways kind of window, the panes of which pop right out for easy cleaning. So while the unit fits in there, it's got about five or six inches of "head room" which covered up with cardboard for the time being. What's the best way of permanently (or at least seasonally) blocking off this area? And how to seal it up so cold air stays in and warm air/hornets/squirrels stay out?

Thanks in advance!

Can a single AC keep my apartment cold

jma — Mon, 09 Jun 2008 11:48:50 -0800

Can a single AC keep my apartment cold? I have a 1br apt. My living room is in the front, with a large picture window, south-east exposure. I have a galley kitchen with a half-height wall opening to the living room. The bedroom is in the back, with three 32"w windows. It gets the afternoon sun. A straight hallway connects the living room to the bedroom. Both LR and BR have ceiling fans.

The living room/kitchen area is where I spend nearly all my time, so I need it cool there. The picture window has two double-hung windows on either side, but they're only 19" wide and I can't put an AC in there. The casements aren't an option given the installation requirements.

I picked up a 10k btu portable unit from Costco yesterday, and it sort of works -- the living area is relatively comfortable. It works better with both fans running. But not after running the microwave for a few minutes. Which leaves me with the impression that it's wholly inadequate when I'm cooking.

So, my only other option is putting a proper window unit in the bedroom. The window I'd use faces out to the hallway, with roughly a straight shot out to the living room. But I want it to be *cold* in here. I want to walk in to relief after work. I want to cook and not use sweat as my secret ingredient. I want to watch TV or work at my computer without leaving soppy impressions where I sit.

Would a 12k BTU unit in the BR do that for me?

No, this ISN'T a mortuary, and no this ISN'T a meat locker.

melorama — Tue, 18 Dec 2007 23:29:47 -0800

I want to buy an "official" sign or sticker that implies to the reader that "THE ROOM YOU ARE ENTERING IS GODDAMNED COLD!!!" My clients semi-jokingly complain that the air-conditioning in my office is way too cold. But since I have about $25,000 worth of video editing equipment in front of my Captain Kirk chair, I like to err on the side of keeping the gear cool (I live in a sity where the median temperature is 85-89F, all year long).

It's become a running joke that I have sides of beef hidden in the drop ceiling, as if I'm a video producer by day, and butcher by night. To be honest, I've gotten sorta tired of the jokes, but since they will never stop, I might as well play along until they actually do. So I'd like to put a big sign or sticker (or some other creative thing that I haven't thought of) on my office door that--in a humorous, sarcastic and/or ironic way--says to the world, "yes I know my office is fucking cold, so I'll spare you the trouble of making a snarky comment about it".

I'm looking for things that are actually "real" signs (i.e. butcher shop signs? Antarctic research facility warning signs? Morgue signs?), and not necessarily things that are outright "jokey" signs, per se. But I'm still open to any suggestions.

Links to actual websites where I can purchase the type(s) of signs or stickers I'm looking for are even better!

Is my car's air conditioner releasing deadly fumes or something?

exceptinsects — Tue, 21 Aug 2007 15:42:07 -0800

Is my car's air conditioner releasing deadly fumes or something? When I turn on the AC in my car lately (since we've been having really hot weather), I notice a sort of burning in the back of my throat. I don't see or smell anything.

This seems to happen on either fresh air or recirc, but if I just run the fan, I don't notice the problem.

I'm going to take it to the mechanic, but I wanted to know if I should be worrying about it. (Generally I try not to worry about things.)

Is it some kind of coolant?

How to calculate air conditioning efficiency?

woodblock100 — Thu, 16 Aug 2007 18:20:45 -0800

Need some advice on how to calculate 'efficiency' of a potential home-brew air conditioning set up. My workroom - well-insulated, no air conditioning - is at 30 degrees (86F) this morning, and this will climb to around 32+ this afternoon.

Just outside, directly below my windows (I'm on a very steep slope) and seven meters below my floor level, is a small river. It's not so deep, has good flow though, but with the hot sun on it all day it's not so cold. I just checked, and it's 23 degrees (73F). That'll probably climb a couple of degrees later in the day.

Is it worth my while to investigate the possibility of working up some kind of system where I pump water up from the river, and run it through a heat exchanger to cool this room? Or am I going to spend so much electricity on a pump and the exchanger, to negate the benefit I will get from that 7~8 degree difference in temperature? (In other words, is there no advantage to just buying/using a commercial air conditioner?)

I need help cooling my garage

RustyBrooks — Mon, 13 Aug 2007 08:14:03 -0800

I'm in Texas and it's really damn hot. I have a workshop in my garage and I need to Get Stuff Done, I need help. It's been a mild summer in austin up until now, and even so, it's very hot to work in the garage. I usually have the door open with 2 good-sized fans blowing, and I still usually lose a few pounds sweating.

But man, starting this week, it's been in the low hundreds and I can't even contemplate going to the garage to work.

Under normal circumstances sweating is a huge problem. I sweat all over wood, machinery, and into my eyes, which combines with sawdust to blind me.

I have an idea that might be crazy and I need someone to stop me if it is. I want to use a small window AC unit in the garage. I know that most of these need to circulate air to the outside to work. I was thinking about making a fake "window" to put the unit into, with ducting to vent it outside, either through the eaves or maybe I'd even cut a vent in the garage door (detachable of course)

My goal here is not to air condition the outdoors, just to bring the temp in the garage to below 90. This would necessitate closing the garage door which is OK for most things (I only need it open if I'm doing a lot of work on one side of the workbench, or if I'm cutting full sheets of plywood)

Anyone done anything like this? Any alternate solutions you can think of aside from this?

How do I get even temps in my 2 story house?

mathowie — Sun, 22 Jul 2007 14:52:27 -0800

How can I make air conditioning work better in a 2 story house? I live in a newish 2story house with a modern air conditioning/heat system. There is an adjustable baffle that controls air flow between floors, and it works well in the winter to direct more heat downstairs but in the summer even when directing all cold air to the upper floor, the upstairs is 5-10 degrees hotter than the first floor.

Ideally, I'd like even temps between floors. I've heard of houses with separate air conditioners for each floor but can those be retro fitted or does it have to go in during construction? Is there any other option to get a cooled down 2nd floor without freezing the first floor?

How Do I use the cool air in my basement to cool my house?

storybored — Wed, 18 Jul 2007 14:38:50 -0800

How can i use the cool air in my basement to cool the upstairs rooms in the rest of the house? It's 66 degrees in the basement but a lot hotter upstairs. I don't have AC and the house has antiquated water-based radiators rather than air ducts. But it sure would be nice to move the cold to where the hot is. Ideas?

Must my lanlord pay for a hotel during miserable heat?

bryanzera — Thu, 05 Jul 2007 18:00:59 -0800

Due to a yet-to-be-correctly-diagnosed problem with the electrical system in our house, our air conditioner does not work. This is a Big Deal in Central California right now. Can we reasonably expect our lanlord to pay for a hotel for us? Our lights started flickering when major appliances kicked in and our air conditioner compressor wouldn't work. After our lanlord replaced the AC unit, nothing changed. Our lanlord is telling us now that it could be up to 5 days before the city comes out to turn the electricity off so that his electrician can diagnose the problem.

It's now 95 degrees inside our house. Fans only do so much. Our dogs are panting constantly and we are uncomfortable. My former dealings with our lanlord lead me to believe that if I asked him to put us up in a hotel until this issue was resolved, he would say "No". I pay money every month to be sheltered from the elements and we are not sheltered from the heat

Can we run our window unit AC indoors, as long as the vent points out at the screen?

croutonsupafreak — Thu, 31 May 2007 18:47:41 -0800

Our homeowner's association doesn't allow window air conditioning units to be mounted outside of dwellings. But with our built-in inside window ledge, we can put our AC window unit right against the screen, keeping it fully indoors while still venting outside. Are there any health or safety reasons why we shouldn't do this?

How can I survive a hot, hot summer without cool, cool AC?

Deathalicious — Tue, 29 May 2007 00:09:37 -0800

Does anyone have tips for surviving a summer in very hot temperatures without AC? I'm in Cairo and unfortunately it looks like the only apartment I can get my hands on has no AC at all. I know in these cases the normal suggestions is "get a window unit" but I have no idea whether this is in fact possible, both from a logistical and economic standpoint.*

Here are the lovely temperature details: temperatures in Cairo during the summer are never below 30C (86F) during the day and generally hover well above the 35C (95F) mark. Many days are closer to 40C (105F) and I've been told that the temperature will get up to 45C (113F) a few times over the summer.

I've survived one 41C day already, but I did have AC although I spent much of the day hanging out in the front hall of my apartment building, which didn't have any AC. Walking outside in the heat was nearly unbearable, I couldn't believe how hot it was.

So, if anyone out there has experience living in very hot weather, that would be greatly appreciated. I'm perfectly comfortable in 25C (77) - 30C (86F) weather. Right now it is only 31C and I feel "hot" but I'm not sweating all that much, if that helps give you a frame of reference.

* That being said, if it turns out getting a window unit is possible, I will certainly go for it and put my experience here on the page for posterity