We had a ten year old 5000BTU window unit that quit working last summer. We replaced it first with an 8000 BTU GoldStar, which did virtually NOTHING to cool the room (the old unit would take the temp down to 60F on an 85degree, humid day. The new unit might have taken the temp down five degrees or so. We returned the unit back to Home Depot and purchased a Frigidaire 9000BTU unit (which somehow fit in our window) and it did NO better. Our bedroom is only twelve by twelve. I know that regulations require a “new” type of freon, but that should make them ineffective (our auto air is just fine). The real problem seems to be that they only “cycle” on to cool air mode for brief periods of time even when the target temperature as not been reached (the old one would run the compressor until the target temp was reached). Other than central air are there any window air units that still work? IF not what is the “cut off” date when these started going down hill (if that’s the problem).
Huh. We bought a new window unit last year. It not only cools down the room it’s installed in, it cools off all 1200 square feet we have.
One of the following may be your problem:
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The place you’re buying them from is crap - try to get your money back and go elsewhere.
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You’re buying the wrong size for your room. I think this is unlikely, but double-check anyway. If anything, err on the side of too big rather than too little.
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You’ve got one of the new-fangled digital control models and you haven’t adjusted it properly
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You’re getting massive, massive air leaks around the unit. You have to seal the unit and window thoroughly, otherwise the cold leaks out and the hot leaks in. When we sealed our window area we got an enormous jump in efficiency.
Um, what Broomstick said. The window air conditioner in my office cools the entire downstairs quite nicely (and has been doing so since 1996). When I close the office doors to keep the “cool” in here it gets downright frigid.
**I think an A/C guy will come along shortly to tell you your unit is too big.
I kid you not.**
If 5000btu worked and is the right size for your area, that’s what you should have replaced it with.
Whether it has newer technology and diff freon is irrelevant, since a btu is a btu.
Home a/c’s were R-22 which was not the really cold R-12, newer freons are pretty compairable w/ 22, so I don’t think that’s the issue.
2 things come to mind:
1 -very likely- Air is short circuting, meaning the cooled air is somehow getting sucked back in to be re-cooled instead of going out into the room. This would cause the cycling you are stating. As an experiment get a fan to blow the cooled air to the other side of the room, or at the very least don’t point the outflow vents down.
2 - the coils are freezing up, if there is way too much humidity this will have to be corrected before the a/c will work.
Keep in mind that, when choosing a room air conditioner, size is important. A unit that is too small will run continually without cooling the room effectively.
On the other hand, if you buy a unit that’s too large for the space you’re cooling, it actually will be less effective than one that’s the correct size. Bigger isn’t necessarily better.
Air conditioners work by removing both heat and humidity. Humidity condenses from the air when it passes over the air conditioner’s cooling coils. So a unit that is too big will cool the room so quickly that it won’t have the opportunity to remove as much humidity from the air as it should. As a result, the unit will keep turning off and on and the room will feel damp, clammy and less comfortable. A properly sized unit, on the other hand, will remove humidity effectively as it cools.
http://www.consumerenergycenter.org/homeandwork/homes/inside/heatandcool/windowac.html
bolding = mine
Can you provide any further insight as to how this can be true? I can only imagine a larger unit would cycle on and off more frequently, I WAG. A 10,000 BTU unit would remove twice the heat in the same time as a 5000 BTU unit. So, if oversized, it may cycle more frequently, wouldn’t you figure?
Is there any reason to support that a larger unit cannot do the job of a smaller unit…even if an oversized unti might not be the most economical choice?
- Jinx
It’s been my experience that too many BTUs will still cool the area, but the RH level will remain too high. In other words, it will be cool, but damp.
I was going to make Philster’ spoint, but I’ll have to pile on instead.
Your AC is too big. An oversized AC will rapidly cool the local area, and shut down. Not only does this prevent the coils from drying off, and leave the room humid, but the circulation from a short run time is inadequate, leaving most of the room warm.
I don’t wish to be insulting but. . .
I have a friend who was on the board of a community owned nursing home. He tells the story of a state inspector coming out and writing them up because the A/C doesn’t work.
The manager gets three different A/C guys out and none can find a problem.
Eventually, they get the state inspection back to the home and they quickly find the problem.
The state dude had turned the dial in the wrong direction.
Jinx, my link helps explain it, and Nametage is all over it as well.
Too many BTUs = uncomfortable. Humid rooms will feel warmer and uncomfortable.
Too big = uncomfortable.
HVAC guy…where are youuuuuuuuuuuuuuu?!
Fascinating! I’d never heard of this. I’ll jump on the dogpile:
According to Philster’s link, your new units are waaaay too big - you’ve almost doubled your BTU rating! A 12 x 12 room yields 144 square feet - the California Energy Commision recommends a 5,000 BTU unit. In other words, what you had before. A 9,000 BTU unit is recommended for rooms 350 to 400 square feet.
I concur with those who say you’re buying an A/C unit that is too large, and for the reasons stated above. I did extensive research on this subject a while back for another thread here. In the process, I found several websites with BTU calculators, including this one at the US Department of Energy.
I could stand four foot away from the unit, and the cold air would literally “hurt” the skin on my face if I stood there to long. In addition, I could manually “turn up” the compressor so that it ran essentially constantly (it never could reach the shut off temp) and this gave a very cold room (at night when we wanted it). However, with the two new units that we tried, even when I set the temp down to some outragiously low level (like 62 degrees on an 85 degree day) the unit STILL cycles. I think the difference is that my old unit had three advantages:
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It’s blower blew harder and thus circulated the air better.
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You could essentially override the “energy saving” features so that the compressor would run constantly on hot days. Seems like the newer units cycle no matter what (forced energy savings).
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The darn thing blew colder. To put it in perspective we have another 8000BTU unit that cools the entire rest of the house pretty good. If you try to stand in front of that unit for more than thirty seconds the sensation again is painful to the skin. The newer unit has “cool air”, but not this “artic blast”.
Having said all of that I will take your advice and get a smaller unit to see what happens. Can anyone advise any specific brands? Also will higher energy ratings tend to work worse or does this parameter simply not matter.
Just a suggestion here. Remove the front cover and filter, and make sure that there is not any packing material that is covering any part of the filter (front or back) and the air flow is not obstructed.