Buying Window Air Conditioner

[TromboneAl]

Hi from Kansas City.

DD is looking for window air conditioners on Craigslist. Any advice?

Which is more efficient: a larger unit running on a lower setting (e.g. Low Cool) or a smaller unit running at max?

Thanks,

 

[REWahoo]

Hi from Kansas City.

DD is looking for window air conditioners on Craigslist. Any advice?

Which is more efficient: a larger unit running on a lower setting (e.g. Low Cool) or a smaller unit running at max?

Thanks,

Neither.

You need to size the A/C for the area of the room. Too large or too small are both less efficient than "The Goldilocks Solution".

To cool this area............. Look for this size air conditioner
100 to 150 square feet ..........5,000 BTUs
150 to 250 square feet ..........6,000 BTUs
250 to 300 square feet ..........7,000 BTUs
300 to 350 square feet ..........8,000 BTUs
350 to 400 square feet ..........9,000 BTUs
400 to 450 square feet ..........10,000 BTUs
450 to 550 square feet ..........12,000 BTUs
550 to 700 square feet ..........14,000 BTUs
700 to 1,000 square feet .......18,000 BTUs
1,000 to 1 400 square feet .....24,000 BTUs

Window AC

 

[Nords]

DD is looking for window air conditioners on Craigslist. Any advice?

I'm a Craigslist fanatic, but some things might be better bought new.

From a buyer's perspective, I'd be a little concerned about why the seller is ditching their air conditioner. They're probably buying a better A/C system and burdening you with the old one's inefficiencies-- or "that funny noise it's started making more often".

I guess you'd want to hear a seller's reason like "Gotta pay for my dialysis treatments"...

 

[REWahoo]

To follow on with Nords comments, newer might also be higher efficiency. Plus new window units are relatively inexpensive - even for a recent college grad...

 

[Sue J]

My son bought a wonderful Samsung window A/C unit for about $130 2 years ago. He chose the size by using the guide for room sizes, like REWahoo posted. At Best Buy they had them set up on a rack with an outlet nearby so we plugged in each one and tried them out for the noise factor. A few were horribly noisy. All put out plenty of cool air and all had digital controls and a remote. The Samsung was the quietest. He got it at Lowes because we had a giftcard he could use.

 

[JOHNNIE36]

New window A/C units are pretty reasonable in price. I paid $250 two years ago for a new Frigidaire unit (8000BTU) at Lowes. You can't just go by square footage. I used that formula and the unit doesn't do the job. Reason? Metal roof, insulated but still aluminum and windows all around. All single pane windows that I had tinted and not went to the 100% reflective film on the west side.. Helps but A/C still has to run all the time. I'd go bigger but can't fit one into the same space which is critical.

 

[samclem]

Oh, this is a tough time to get a new unit cheaply. I paid $149 for a 10K BTU Samsung unit at the end of the summer two years ago at Lowes, that's the best time.

Unit sizing--it's important that the unit stay running long enough to sufficiently dehumidify the air in her apartment. An overly large unit will quickly cool the place off, but because not enough air goes through the unit, the room/apartment will feel cool but clammy. Plus, a smaller unit will tend to do a better job of equalizing the temp in the whole apartment (because it is moving air for a longer time), while an oversize unit will turn off once the air near the unit gets cool (cold), but the rest of the apartment might still be hot.

If you really want to analyze this to death (as ER types are prone to do), here's a detailed calculator that will let you compute the cooling load for her place (I don't know if you have to put any entries into the "Step 5" box, as those compute the heating load). If she's got multiple rooms, a box fan on "low" can effectively and quietly spread the cool air around. It makes sense to get a unit a little bigger than the max called for, but don't oversize it by a lot.

One other thing--some of the very large units require 220 VAC. Don't get one of those unless she's got a 220 VAC receptacle near the window.

 

[TromboneAl]

Great info, thanks.

She analyzes the situation like this: Based on her size requirements it would cost (one 6500 BTU unit for LR one for 5000 BTU for BR):

$460 for two new energy star air conditioners.
$250 for two new non-energy star air conditioners.
$150 for two used (energy star??) air conditioners.

Based on that, and the fact that she has less money now than later, and doesn't know for sure whether she'd be moving in a year or two, the used option sounds good to me. I don't have enough data to calculate the payback period for the more expensive options.

 

[wallygator69]

Hey,

I'd be careful with a used one if noise is a factor (ie. bedroom). I bought a brand new one at Costco for cheap money but it sounded like a freight train. Then to top it off, when the compressor kicked in or out it made a clunk that would wake me up every time. I returned it the next day. With a used one you'd probably be stuck...

Good Luck.

W

 

[Dawg52]

I bought one at Walmart a couple of years ago for my bedroom. Pretty cheap and does the job. Even has remote control. I don't mind the noise, drowns out the gun shots down the street.

 

[Sam]

$460 for two new energy star air conditioners.
$250 for two new non-energy star air conditioners.
$150 for two used (energy star??) air conditioners.

I would go with the $250 options.

1) New: will most likely not having problem in the next few years.
2) The $210 saved (over the $460) will more than cover the difference in energy consumption in the next few years.

BTW, I installed a new Samsung Energy Star 6000 BTU unit last year. Bought it at Walmart for ~$130 (bought at the end of the summer). Very happy with it. Power consumption is only ~350W when the compressor is on.

Sam

 

[Rambler]

I agree with Sam. The new ones will probably be a better value, and quieter. It would take too long for the energy star type to pay back, esp if she thinks she may move or no longer need them.

On the other hand, if she is happy to deal with the unknown, then maybe craigslist. I wouldn't, but that's me.

R

Note: my dad got a couple at the beginning of the summer last year for $99 each. Home Depot, 5k BTU.

 

[TromboneAl]

Here's the bedroom unit she got for $40 (craigslist). Works great so far. The shaft of the lower knob had been broken, but we fixed it with epoxy and tape.

One down one to go.

 

[HFWR]

The shaft of the lower knob had been broken...

I hate when that happens...

 

[NW-Bound]

I hate when that happens...

Didn't epoxy and tape work for you?

 

[TromboneAl]

Didn't epoxy and tape work for you?

Yes, it worked perfectly.

 

[NW-Bound]

IHFWR, did you get that?

It's nice to know you can fix it, but of course it is better not to break it in the first place. I still suspect it wouldn't be the same.