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Window air conditioner as heat pump

I have added insulation in the ceiling of the basement which makes the house more uniform in temperature. And reduces the amount of heating required. But that allows the basement temperature to drop a bit. And it is a bit too chilly to enjoy working in the basement at least during the winter.

So when I saw a 5000 btuh window air conditioner for $15 at the Habitat For Humanity store, I bought it and installed it backwards in one of the two basement windows. It does work, but not as well as I hoped. The basement temperature is about 55 degrees at this time of the year, and running the air conditioner for about four hours on a warm day brings the temperature up to about 60 degrees. But on a cool day when the weather is about 60 degrees outside, the air conditioner produces almost no heat in the basement.

So not a complete waste of $15, but not a unqualified success.

Dan

Reply to
dcaster
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Youll decrease the life expectancy of the a/c unit if you use it like this..just so you understand. Im assuming your basement area isnt too large in which case a fan-forced portable electric heater might be more effective and permanent for times that you occupy the space. That would be your cheapest way out. If you want to make it more professional and more economical, then a dedicated Heat Pump Window Unit is the way to go ; I got the smallest 240 volt powered Window Heat Pump Unit with backup electric resistance heating i could find for my 200 sq. ft. bedroom which I use while im sleeping to avoid running my central 4 ton capacity unit for the entire house. The cooling capacity is 9,000 btus and on the heating cycle its 12,000 btus . Only draws 3.5 amps when running using the compressor .

Reply to
ilbebauck

Heat pumps have a habit of frosting over the evaporator. The heat pumps designed as such, have defrosters, and freeze sensors and other parts that window AC don't have.

Maybe move the insulation to the cellar walls, and put in a damper so you can have some heat off the furnace, while you are working?

Christopher A. Young Learn more about Jesus

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So when I saw a 5000 btuh window air conditioner for $15 at the Habitat For Humanity store, I bought it and installed it backwards in one of the two basement windows. It does work, but not as well as I hoped. The basement temperature is about 55 degrees at this time of the year, and running the air conditioner for about four hours on a warm day brings the temperature up to about 60 degrees. But on a cool day when the weather is about 60 degrees outside, the air conditioner produces almost no heat in the basement.

So not a complete waste of $15, but not a unqualified success.

Dan

Reply to
Stormin Mormon

mini-split heat pump or a window unit heat pump would be a whole lot more benificial. No, its not gonna cost $15, but it will keep you comfortable.

Reply to
Steve

Using window AC as heat pump the AC that was not design for heat pump. This may be surprise to some Techs. but lots of this units have critical charge now there is many units with critical charge however some units with critical charge actually if temperature drops below certain range unit will run out of liquid and it will start to pass mix liquid with gas results head pressure will drop. Once head pressure drop naturally temperature of condenser drop also. This may result in some freezing of Evaporator but not necessarily depend on few other factors in design. SO IT IS NOT IDEAL USE OF WINDOW UNITS as HEAT PUMP!!!

Reply to
grumpy

That is pretty much what I was saying. But when the outside temperature is 70 degrees F. or above it does work as a heat pump. Of course I could just use a fan to pull in the outside air, but that would pull in the humidity too.

Today the outside temperature was about 70 degrees and the air conditioner raised the basement temperature 6 degrees making it comfortable to be in the basement.

Dan

Reply to
dcaster

I think the air conditioner will work to raise the basement temperature until next Fall. Mean while I plan on insulating the top half of the basement walls when I have time. Somewhere on the internet I read that is better than insulating the whole wall from a humidity standpoint. It also is less expensive than insulating the whole wall.

I have a few far out ideas about solar panels. but that takes time. Right now I am focused on adding more area as a veggie garden. The air conditioner did not take much time or money, and it seems to work some what better than electric resistance heating when it is warm outside.

Dan

Reply to
dcaster

Of course, you don't want to add moisture under those conditions. You need to drain the water by the evaporator.

Greg

Reply to
gregz

And you can't simply plug an electric heater in why?

Reply to
Brian V

You realize that the backwards AC, the evaporator is outdoors. The humidity drains to the condensor (indoors) where the slinger ring fan wets the condensor (indoors) and reevaporates the humidity. So, the backwards AC takes out door humidity, and puts that moisture indoors.

OTOH, if you were able to find a way to drain the evaporator into the ground, you'd be dehumidifying the great outdoors.

Christopher A. Young Learn more about Jesus

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Of course, you don't want to add moisture under those conditions. You need to drain the water by the evaporator.

Greg

Reply to
Stormin Mormon

The air conditioner seems to work as well as two electric heaters and uses less electricity than one electric heater.

Dan

Reply to
dcaster

No, I did not realize that. When I first installed it, the condensate was draining inside. So I modified the shelf I had made by putting a lip on three sides so it now drains outside.

If I get ambitious I will take the case off and see if I can easily do something to increase the efficiency. Thanks for the info.

Dan

Reply to
dcaster

I got most of my early experience on window units, some what familiar to me.

Living in a trailer, in humid NYS. My living room AC, the evaporator drains out on the ground. One in the bedroom, has the standard slinger ring set up.

You may be able to drain the AC into storm drain, or other way to get rid of the water. Dripping back outside sounds like that works, too.

Christopher A. Young Learn more about Jesus

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No, I did not realize that. When I first installed it, the condensate was draining inside. So I modified the shelf I had made by putting a lip on three sides so it now drains outside.

If I get ambitious I will take the case off and see if I can easily do something to increase the efficiency. Thanks for the info.

Dan

Reply to
Stormin Mormon

And you are sharing this information with us? Why?

Reply to
PaxPerPoten

The thermostat on your AC is designed to cut off the compressor when the indoor temp is below a certain temperature. In this case that is the outdoor temp, so if it was cooler than say 65 outside, it won't run. The fan may run, but not the compressor.

So, what happens if you bypass the thermostat? Because heat pump temperatures are much lower than when you are air conditioning, pumping heat from an already cool place will drive the evaporator below freezing, and freeze up the coils.

Heat pumps have a defrost cycle (a temporary reversal usually) to counter the evaporator freezing. Your window AC does not.

Note that window ACs usually have bent over fins, from handling. What could have been a good AC won't work well with obstructed air flow through the condenser. Fixing fins and cleaning coils is basic maintenance.

Use your AC for what it was designed for. Get a space heater.

j

It does work, but not as well as I

Reply to
j

It seems like this would be exactly what ought to be shared here. It is related to HVAC and it is an Alternative use of HVAC. So it seems like something which is exactly on topic for a group called Alternative HVAC.

Dan

Reply to
dcaster

Why would a comedian like you be interested in this group, when you can find so many NG's that more fit your character? Try alt.homeowners!

Reply to
PaxPerPoten

The other issues are that the controls and the "not weather proof" side of the AC is now outside. And that the condensate dump is now in the basement.

Because they are trying to get at least "some" efficiency out of the unit, the outdoor coil is sized to keep the temperature difference across it relatively low.

It's not really a good use for an AC.

Since most heat pumps loose efficiency as the outdoor temp goes down, the cooler it is outside the less heat you will get.

A resistance heater would be better for your use, if it's just intermittient.

An "infrared" heater that just heats you would be even better.

Reply to
No Body

So long as it isn't one of those overpriced cube faux "infrared" heaters that don't emit any actual infrared light, just warm forced air.

Reply to
Daniel who wants to know

Made by real Amish?

Christopher A. Young Learn more about Jesus

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So long as it isn't one of those overpriced cube faux "infrared" heaters that don't emit any actual infrared light, just warm forced air.

Reply to
Stormin Mormon

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