any advice on buying a window AC unit?
We have to buy a window unit for our house. We have Central AC but it's not keeping up and we can't afford to upsize it right now. So until then I'm researching which window units to buy. Any advice or anything to cut through all the marketing spam and AI copy that I have to wade thru?
DO NOT BUY ONE THAT SITS IN YOUR ROOM. The ones that sit in the window are better because the heat is already outside instead of having to go through a tube.
get one rated for the room size.
I have one for an attic room that gets around 100°F without one. it's about 100sqft and I'm running a 9000BTU system. with the unit it stays around 71-74°.
stay away from "Mr cool". they've had lots of defects from factory.
I would get something local, probably Walmart. reason for that, if you have any problems you can just take it back.
All I can really say is to avoid the floor models, since they put the hot part of the conditioner inside your home, thus have to work a lot harder
See Technology Connections (Piped) for an informational video
My experience with these units is that they're horribly unreliable too. I worked in an industry where we'd use these for temporary or emergency cooling for server rooms and I don't know if I ever saw a model last more than a year. A lot of window units are pretty flaky too, unfortunately, but you'll probably at least get 2-3 years out of one.
I know it's a considerable cost increase and installation, but still way cheaper than upgrading your central A/C, and way more efficient, quiet, elegant than a window unit: add a mini-split to the room. I added a Mitsubishi to our hot office with tons of electronics and it's one of the best home investments I made.
Don't do it at this time of year.
This is a fact. It’s absolutely the highest priced time to buy any air conditioning. Everyone is buying so they have zero incentive for true sales.
Not what you asked, but you might check that:
Can't improve insulation? Did you mean can? If so, yes, that's on the to do list. We need better windows too.
Yes, those are good tips thanks.
You should have at least 16” of insulation in your attic. Check for regional guidelines on this as it depends on where you live.
Insulation settles over time so the older the home the less your insulation has air gaps that do the work. This is the lowest cost form of improving your situation and the cost is mostly in labor since it’s hot work. Buy insulation yourself and do the work yourself to save a LOT. You can rent insulation blowers from big box hardware stores and they usually have deals where if you buy a certain amount of insulation the rental is free. Early morning is the best as it’ll be the coolest, drink lots of electrolytes when you start sweating. New insulation has rolled ends so it’s not the super itchy type of yore. It’s not terrible and you’ll be glad you did it once it’s over. Having a hand is not essential but makes it a lot easier.
We insulated our garage with paper backed rolled insulation for 2x4s for not much more than $300 over a few months (I did the labor) and it improved the temp swings by ~40°. Absolutely great investment and it was super easy to do. All I needed was a stapler, tape measure, utility knife, a ladder, and myself.
Buy a meat thermometer and put it in your floor or ceiling vents. You should have a 20°F+ drop from what the room is at to what is coming out of your vents. This is known as a delta T (temperature difference). If it’s lower you need to get your AC checked out by a reputable company with warranties and guarantees. Chuck and truck is always a waste of time and money, they’re lower cost up front but you will regret it most of the time. If your system is 15 years or older you may need to get it replaced as repairs are often more costly than it’s worth and all newer system are much more efficient, saving you $ in the long term.
Duct sealing is another thing that can improve your AC issues. Most ducts leak 40% due to holes in joints etc. The air you want to get to the furthest part of your house isn’t getting there at its full extent. Look for companies that Aeroseal. This will be cheaper than a mini split but can be as effective. You’re looking at a few thousand depending on the size of your situation.
On top of that, some rooms don't have proper cold air return to the furnace, meaning those rooms don't get proper air circulation and can be the reason for a room being warm. I'm experiencing this right now. One bedroom has a cold air return on the other side of the wall, but nothing in the room itself, and it's the hottest room in the house. I gotta cut an entry to that cold air return duct.
Just don't get a portable unit. They suck and are just a waste of money most of the times.
These are portables if you're unfamiliar.
While the dual hose ones are better, I agree that these all kind of suck because you have the compressor inside and it's always the loudest part of an AC.
If you get an expensive one with both in and out ventilation through the window it can be good. But you’re spending a lot more than just a window AC at that point. The cheap ones actually vent your cold air outside.
I got a couple of $150 cheapo units at the big box stores to supplement our central air during heat waves, have been just fine. 5k or 6k BYUs at least.
This is correct, you need a “ closed” loop of outside air (by this I mean, the unit does not vent inside air through the condenser coils to the outside) and the two-pipe units are the only way to achieve this.
If you go that route, be aware that these usually collect the evaporator moisture and you either have to manually empty the bucket or pump it to a drain (you can connect it to a laundry machine drainpipe for example). If that isn’t possible and your indoors isn’t sealed well you might be emptying it a lot. Still, there are situations like smaller basement windows for which this is the only practical solution.
Just don’t get a portable unit. They suck and are just a waste of money most of the times.
Get a dual-hose unit if you get one. There are a lot of companies selling single-hose units. Those are a lot less efficient and aren't much cheaper. I would guess that in a situation where they get any kind of meaningful use, a dual-hose unit pays for itself quickly.
I don't think I'd agree that they suck, but if you can use a window unit --- not all rooms and windows are amenable to this --- you normally want a window unit instead of a portable unit, unless you must take down the AC unit on a regular basis. Less noise inside, more energy efficiency.
Idk, I got one made by Midea and it's pretty good imo. Granted, we have casement windows (the ones where the window slides to the side to open, not up/down) so the usual window units weren't an option.
Be aware that most window A/C units are power hogs. Expect to see a significant rise in your power bill. It might be cheaper to have your home A/C unit serviced instead. Could it be low on freon? Would it benefit from having the coils cleaned?
They’re mostly all made in one or two factories in China. Midea and another one.
When it comes time to replace the AC, consider getting one that’s reversible and runs as a heat pump. You don’t need to use it, but it shouldn’t cost much more and gives you flexibility.
Make sure you buy one with enough cooling power to cool the room it's in. If it's a small bedroom you'll want 5,000-8,000 BTU and if it's a larger area like a living room you'll probably want 12,000-14,000 BTU.
I just put a 12,000 BTU unit in my living room because it's open to the kitchen and it's about 550ft².
A good rule of thumb is 20 BTU per Ft², so my 550ft² living room/kitchen area would require at least 11,000 BTU.
Call a service tech to look at your central. If it’s not keeping up then it might be cheaper to fix the issues with it over buying a window unit and paying the electricity to run it.
Central Units are typically much more powerful and therefore need to run less, and if it’s something simple like it need to have the condenser cleaned out or the refrigerant recharged the cost to just get it done is much less than the cost of window units plus electricity plus your time to install and remove them
This isn't actually necessarily true if you just need specific cooling.
If for instance, you just care about cooling your bedroom for sleeping, then it can be more efficient to install a window unit in just that room and let the rest of your house be warmer. A mini-split would be more efficient than a window unit for that role, but they're also a lot more expensive and permanent.
Yeah for new installs but service for the existing unit might be like $200 for a cleaning and it’s certainly going to be cheaper to run in the long run
Window units are built to fail, are mold prone, use an excessive amount of electricity comparatively (even the newer inverter ones) and a higher risk of injuring a person or damaging the building. Also their smart features often entice people to install apps that track you to sell to advertisers. So not only are you buying an inferior product but they’re also capitalizing of spying on you.
(tl/dr: fuck Frigidaire lol)
So you have three options, I'm going to break them down just because I think comparing all three is helpful for long term planning, but skip to the end for advice on a specific window unit.
If it were me personally, and I owned the house, and I was worried about cooling my bedroom, and I had the money and somewhere to mount the compressor, I would buy a DIY mini split system. I will always want my bedroom to be cold for sleeping and the rest of the house doesn't need to be that cold (and vice versa in winter since they're heat pumps that go both ways). The only real downsides are the very light fan noise from the blower unit, and the upfront cost, though that can potentially be mitigated if you live in a jurisdiction that offers some type of home retrofit or heat pump grant (worth checking!).
That being said there's a bunch of caveats and criteria there that I personally didn't meet, so I bought one of those Midea U shaped units that everyone talks about and am honestly very happy. There was a massive recall recently, but they're adding drains to fix the issue, and these units otherwise are way better than most other window units, though they only work with windows that slide up and down vertically.
*But unlike most other window ACs, the U shaped units have the window sit between the outdoor unit and the indoor unit which blocks most of the noise from the compressor, lets more natural light come in, and doesn't require blocking the sides. They're also very efficient with a CEER rating of 15.
Even despite the recall they're still what I'd personally recommend, you might be able to find one second hand.
Also note that I don't consider a portable air conditioner an option. They're terrible.
I read you're planning on upgrading your insulation and windows, and speaking from personal experience those two things make a huge difference. They're also somewhat expensive to do, so I'm guessing you're planning on doing these changes within a year.
In which case, you only need this window A/C for about 2-3 months. You might as well go with the cheapest one and save the money. Just make sure to get something to seal the door too so the cold air doesn't leak out.
Most window air conditioners come from like 4 factories anyhow. Only if you're planning on keeping it around for years do you want to look for something specific.
What's your budget? There are a lot of options to narrow down. I have an amazing unit that was around 400 bucks but you can find reliable ones a quarter of that price, or 4x.
What size is your central AC (usually measured in "tons") and what's the total area of the space you're trying to condition? Single story or multiple stories?
We have one in an upstairs bedroom from midea, the window slides right between the front and back of the unit and it's excellent. Our power consumption didn't increase too terribly much and it's actually decently quiet.
Not gonna put the model here but just look for U shaped window units. It has little legs that go outside.
Don't get the inside standing units, they're massive, loud, power hungry, and most of them are less effective than even the cheap window units.
The U shaped units manufactured by midea were all recalled and are not currently available for sale.
You might want to look up the recall and get the repair kit. They were recalled for excessive mold build up.
It seems the recall for the mold was essentially forgetting to put a drain for excessesive condensate. I havnt gotten a response yet. Did you get a response from them? Sucks that unit is awesome. And quiet. I thought it was funny they didn't leave condensate tap to run a drain. I kinda assumed they figured out how to evaporate it in away like a refrigerator. They are made really well otherwise and have great user controls. Even the mounting bracket are next level.
Other comments seem to have covered the advice around checking insulation and system charge, so I'll say that if you need to get a window unit make sure it's an inverter unit; they're typically advertised as ultra-quiet. The reason you want an inverter air conditioner is purely the efficient gains you get over a traditional on/off compressor; they use around half the electricity in some cases for the same cooling.
All of the U-shaped units from various brands use inverter tech, but they might be hard to find because a lot of them are rebranded Mideas. LG's ThinQ "dual-inverter" units are also very good, I have one that's served me well for a couple years and it's very quiet. You can barely hear the compressor start up at all aside from a faint electrical whine for a few seconds and the sound of refrigerant moving through the system. The fan moving the air is the loudest part by far (and it's not bad).
All of that said, consider replacing your central ducted unit with a multi-head mini-split system in the long run. For residential use they're typically the most efficient you can get, and you have the bonus of being able to control room temperatures individually. A mini-split system uses inverter tech too just like the good window units. In fact, the U-shaped window units are just miniaturized mini-split systems in a rigid housing.
Midea recently recalled its u-shaped unit, so be wary of used ones (I have one and now have no way to get rid of it).
There are also these GE ones that are like upside-down U’s to keep out of the way of the window; but between the unit blowing air so low as to not affect the rising hot air in the room and the fact that they have to pump the condensate up and over the window sill make me think they’re not a great investment…
All of that said, consider replacing your central ducted unit with a multi-head mini-split system in the long run.
Mini splits don't provide ventilation, whereas ducted systems do. In general, if one can have a ducted system, I'd rather have that. The major problem with ducted systems is that ductwork takes up a lot of space, so it's hard to stick into an existing house; much less of an issue if you can build it in during construction. A mini split is less invasive to an existing structure.
The U-Shaped units were also all recalled due to mold collecting in a drainage area. Source: Consumer Reports, because yesterday I was researching which on I could get for my stupidly narrow windows, in my stupid new old house. Went with this one:
LG - 330 sq. ft. 7,600 BTU 115-Volt Window Air Conditioner with Cool, Heat and Wi-Fi Control - White
Model: LW8023HRSM
SKU: 6583340 (Best Buy)
I was in the same situation as you at my last house. Central AC was added to a 100 year old house but it was never enough. I got new windows put in, and that helped, but it still got to hot in the summer.
We got this U Shaped Midea window unit and that did the trick: https://www.midea.com/us/store/cooling-and-heating/window-air-conditioners/u-shaped-air-conditioner-ultra-quiet.MAW08U1QWT
It's better than a standard window unit because you can close the window nearly all the way, unlike standard window units that rely on those crappy plastic accordion things.
Best of luck.
I have 3 of these and love them. Unfortunately there is a recall on them for mold (never had a problem with mold in my units) and I think because if it, they're really hard to find now. Amazon has pulled them from sales.
can confirm. mold was growing in mine.
look inside the blower when it's off. mine had all these little white dots of mold that looked like dust, but it was definitely mold.
Been a while since I had to buy one so might no longer be accurate, but an inverter-type window A/C will be more energy efficient than the regular one.
If you install a window unit, your window will obviously be open and there will be a gap between the two panels of your window in which air can pass through. I got these little rubber flappy gasket things with adhesive strips that cover the gap and visually kinda blend in and aren't noticeable. If you search for "door draft stopper" or "window gasket" you should be able to find it.
Check the minimum operating temperature. Most ACs will start throwing hot air if the outside temp drops to 18c/64F. Not a problem if it's going to stay warm overnight but towards the end of summer the night temps can dip fairly low.
Look for a high SEER, https://en.wikipedia.org/wiki/Seasonal_energy_efficiency_ratio
Window AC can be much cheaper to operate than central even if the window unit is less efficient, since it's cooling just one room instead of the whole house.
Where I am, we've had some quite hot days (100 degrees but not much above that so far) and I haven't had to use the AC yet, because it's still pretty cool out at night and the house stays cool enough during the day. That might change if it starts getting hot at night.
Midea U was a highly regarded device until the drainage recall. Not sure how that changes things. There are ac window units you can connect directly to solar. If you already needed a shade structure, that could be a way of achieving two things at once.
I just replaced all my recalled Mideas with GE Profile ClearViews. We've been running them through the current northeast US heatwave and they've been very good. Definitely get one of the inverter driven ones (10 or 12k BTUs I think, the smaller ones aren't).
It’s probably not undersized. You might have a duct leak, insulation gap, air gaps, etc.
You might have rebates in your area that pay for some of these things. One inexpensive thing you can do is run reflectrex across your roof rafters. While you’re up there air seal any gaps into the living space like can lights and hvac vents.
You can also seal your windows with plastic.
You can get a flir camera for your phone to see where the heat is coming in the most.
I mean, can't you just cordon off the hot room and deal with it in the fall? My family did that, I will do it with our master sometimes. If it's too hot home just can't cool everything effectively, so I just close the door to our master and we camp out in the living room on extremely hot days. Uses less power and there's really no real loss.
Check farmers markets for second hand ones, usually very cheap and just need a little cleaning. Look up the units while you are there and check the room size it will cover.