How can I make my in-window AC more efficient?

[CSS]

Okay, so before I get into this, I have cleaned the filter and blown out what I can of my air conditioner.

The AC works just fine well, when it's not hot. That sort of defeats the purpose. This might have you thinking that it doesn't work at all and the cool air is just ventilating inside and the AC is just really half-assed, but when it is dark outside, the AC works fine. It plays in frosty, freezing air like it should when I have it on high.

During the day, the AC is extremely loud. It "powers down" as if it doesn't have the required electricity or something, and it basically does not work during the day, in Florida, when it is hot. Being that it works perfectly fine at night, why is this? What part of the day and sunlight renders my AC useless until sunset?

[ZeroTolerance]

The size of the room you are trying to cool and the lack of insulation in the envelope of your house.

[CSS]

The size of the room you are trying to cool and the lack of insulation in the envelope of your house.
It's not a very big bedroom, I'll get exact figures if you want but I've considered these variables also and I still don't understand how right at about 8PM all the way until about noon things work just fine. After noon and until 8PM, it is insanely loud and after about 10 mins you'll hear it jump and get real quiet while it's still on but it's just not pushing out cold air. Is it maybe because of the humidity and thickness of the air when it's hot? Is it so loud and erratic because it doesn't have the required electricity available to power it? Could I try unplugging some other things?

[ammoniadog]

The condenser coils are probably dirty, which causes the unit to overheat and shut off the compressor every once in a while. To clean the condenser you might have to remove the unit and take it apart and vacuum, blow out, and/or rinse out the condenser with a garden hose. When it gets to this point, most people just buy a new one.

[ewwilt]

I agree with ammonia dog on a dirty condenser coil. The air is pulled in through vents in the sides of the unit and the fan pushes the air through the coil out the back side. Looking at the back of the unit the coil generally looks clean but all the dirt is accumelated on the other side (inside) of the coil. So when it is warmer out the condenser is too dirty to allow the compressor to stay running so, no cooling.

[Kevin O'Neill]

It could be low voltage due to a power company brown out.

Otherwise i agree, probably a dirty condenser.

[wiley9190]

I agree with ammonia dog on a dirty condenser coil. The air is pulled in through vents in the sides of the unit and the fan pushes the air through the coil out the back side. Looking at the back of the unit the coil generally looks clean but all the dirt is accumelated on the other side (inside) of the coil. So when it is warmer out the condenser is too dirty to allow the compressor to stay running so, no cooling.

I would definiatlly agree with this, usually you can remove the panel with the unit is still in the window and acid wash

[wiley9190]

Or the unit will slide out of the casing in the window or wall and just take outside

[CSS]

I would definiatlly agree with this, usually you can remove the panel with the unit is still in the window and acid wash
Can this typically be done by access to the front of the AC? The window is a good 15 feet from the ground outside.

[wiley9190]

No needs to be done from the outside

[catmanacman]

remove the unit and take outside and clean it . or just replace it

[REP]

The way I see it,its enough of a problem for you to have come to us for a solution.
My first question is "has thuis unit ever worked for you in this particuliar window? If the answer is yes you must take the unit outside.Take off the outer housing,tightly wrap the motor and compressor terminal connection and the electrical box or area where the controls are with plastic to keep these areas dry.
Then you spray both coils with water to soak it.then you spray it with some very good cleaner for dirt and oil.Off the shelf stuff.then you rinse it.do it again if it was very dirty. then let it get as dry as it can and reinstall it.
Or you can go to any one of the big stores nan buy a new one.You should look for a life of ten to fifteenn years on it.This time of year you can get a good one for $100 or less.
P.S. I have cleaned hundreds of window shakers and have used acid cleaners but I do not reccomend these cleaners to the casual user as they are some nasty stuff and will corrode anything that the rinse hits like siding or concrete or driveways or bushes or any plants or grass etc. etc. .

[snewman24]

Like Rep said, go get a new one for $100. Small window units are basically throw-aways now. Some can be very hard to take apart and clean well. They're just not designed for it.
Better go buy one before they are sold out. When hot weather hits it doesn't take long for the stores and warehouses to empty out their annual inventory. Home Depot, Lowes, and Sears all carry inexpensive 5000 BTU units - mainly LG (Kenmore) & Frigidaire. I just bought one the other day.

[coolfruit]

personally i use pink stuff and a pressure washer. just spray on let it sit for 5 min. and rinse off. just do not get too close and spray straight on you do not want to bend the fins. if you do not have a pressure washer take it to a car wash. let dry for a day in the sun reinstall and enjoy the cool air. if that does'nt work buy a new one.:.02:

[dan sw fl]

Visit Sears. Do NOT get a unit > 6,000 BTU for a small room.

[udarrell]

Okay, so before I get into this, I have cleaned the filter and blown out what I can of my air conditioner.

The AC works just fine well, when it's not hot. That sort of defeats the purpose. This might have you thinking that it doesn't work at all and the cool air is just ventilating inside and the AC is just really half-assed, but when it is dark outside, the AC works fine. It plays in frosty, freezing air like it should when I have it on high.

During the day, the AC is extremely loud. It "powers down" as if it doesn't have the required electricity or something, and it basically does not work during the day, in Florida, when it is hot. Being that it works perfectly fine at night, why is this? What part of the day and sunlight renders my AC useless until sunset?
Most small window units don't have much air flow; they won't cool a very large area without fans to circulate the air.

Use a 20" fan to circulate the air within & through rooms & back to the units Return Air intake.

You will be amazed at how much area a Half-Ton room unit will cool. My (.5) half-ton cools +750-sf, that's 1500-sf per/ton of cooling.

It has never got too hot or humid for it to keep me very cool & comfortable.

[chuckcrj]

Question: How to make a window A/C more efficient?

Answer: Scrap it out, close the window, and install a mini split.

[dan sw fl]

Question: How to make a window A/C more efficient?

Answer: Scrap it out, close the window, and install a mini split.

Small bedroom

:gah::gah:

Why would anyone recommend a mini-split with minimal (or even negative $$) advantage !?!!

[mamabug]

We are having the same problem with our through the wall AC unit. This will be our 3rd summer in this house. The AC unit is upstairs and we have central air downstairs. The first summer the AC unit kept the area up there COLD. The unit is in the master bedroom but also cools two smaller bedrooms. The total square footage of the upstairs is approx 700 sq feet. We are told there is minimal insulation above the rooms. It was removed years ago by previous owners. We were given a good reason why they removed it and it made sense but I can't remember what it was. None the less, the AC unit worked great the first year. Last summer it worked great as well, until it hit 107 degrees outside. Once we had a string of really long days it would practically stop working completely during the day but come evening it would, once again, run like a champ. We figured the high temperatures were just too much for it. We turned it back on about a week ago. The first few days it worked great. The last couple it is back to being sluggish and not cooling in the afternoons. Its only 86 degrees outside right now and it is already starting to falter. After reading posts here, I may have my husband see about cleaning out the coils before we try alternatives. We really can't afford to replace the unit right now as we obviously need a pretty heavy duty one with the amount of space this cools. It wouldn't even be a problem under normal circumstances because it keeps the bedroom cool during normal sleeping hours. However, my husband works midnights so he is sleeping during the hottest part of the day and lately he keeps waking up miserable.

[paraglider]

Replace freon to higher number freon. Higher number - more cooling.:):):)

[snewman24]

Replace freon to higher number freon. Higher number - more cooling.:):):)

Is that the way it works??? Better try R-1270 then.....mucho BTUs:yes:

[paraglider]

Is that the way it works??? Better try R-1270 then.....mucho BTUs:yes:
What? You didn't know???:bump::grin2:

[mamabug]

My husband and I pulled the unit out and cleaned it up, including using a cleaning solution made for AC coils and a coil comb. We put it back in and started it up. I guess we'll see tomorrow afternoon if that is the answer. The inside back coils were awful though. A thick black sludge came off of them.

When we had it apart I noticed that the unit is 25000 BTU. When I was looking for replacements the largest I found locally was 12000 BTU. If we have to replace I guess I will have to look elsewhere.

[snewman24]

.................................................. ...........
When we had it apart I noticed that the unit is 25000 BTU. When I was looking for replacements the largest I found locally was 12000 BTU. If we have to replace I guess I will have to look elsewhere.

Lowes has one that big (Frigidaire) that some stores carry, & Home Depot has several (LG & GE) but you may have to order online (free shipping). If you end up needing one, order it before they are out of stock for the summer. If you have Menards nearby they carry a 24,5000 BTU in-store. You can check them out at their respective web sites.

[mamabug]

Thanks for the info on where to find the larger BTU units. We live in a small town with not much to offer in the way of shopping so finding things local is sometimes impossible. I will definitely look online at Lowe's and Home Depot. I'd prefer to look in store but our closest (still an hour away) stores are... or were in the case of Home Depot, in Joplin. Thanks to the tornado our best bet would be shopping online.

The unit does seem to be cooling a lot better this evening. As I mentioned previously though, it always performs better in the evening. Tomorrow will be the real test as it is expected to get pretty warm in the afternoon.

[dan sw fl]

http://www.lg.com/us/appliances/air-conditioners/LG-window-air-conditioner-LW1811ER.jsp

If the envelope is any where close to adequate, 18,000 BTU/ hr is more than sufficient.