I agree with you. Huge waste of money.
Plumbing in a window AC Unit to simulate central air
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when we have an outage in texas, I use a big AC unit on wheels, and I plumb the exhaust into the dryer vent of the house. That barely gets the job done in one or two rooms max. His plan will not work in any way shape or form.
Many older furnaces had a fan only option. Check if he has that. If so it’s likely the furnace uses basement air to circulate throughout the house. That was common back then. The cooler basement air would help bring the temperature down. If this is the case then there would be no need to duct anything to the furnace. Just mount the unit and run it and turn on the furnace fan.
With all that said, it’s still a hokey way of doing things.
With all that said, it’s still a hokey way of doing things.
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The reason they are so ineffective is that portable units are cooling air that’s already been cooled. If they have an intake from outside, they are better. But i researched and few units have intake and exhaust from and to the outside, which is how a window unit works
I may suggest that he try the dryer-vent thing - much less invasive than cutting a new hole.
This makes me realize I don't actually understand how window AC units work.
Do they draw in hot air from inside, cool it, run a fan to blow air across the evaporator to inside, and then exhaust the original air outside?
Just support your friend in this endeavor which will lead to failure. That is if he is not willing to consider your thoughts.
You can’t fix stupid if that is the case.
You can’t fix stupid if that is the case.
The air from the evaporator and condenser sides of a window AC is kept separate.
Some have a flap that can be opened to outside air to be sucked inside. The last window AC I saw that had that feature was probably from the 70s, though. I've never noticed if modern window AC units even still have the option of outside air.
No, they pull in air from the outside & blow it over the condenser, the interior air just gets recirculated & cooled/dried more. My old GE & new Haier have an interesting feature-the cool condensate (water) gets thrown up on the condenser by the condenser fan blade, increasing efficiency. As long as you don't mind the water splashing noises all the time!
You're kind of stating that both occur: pull air in from the outside AND recirculate the interior air?? Modern window units do not pull air from the outside, except as noted that a few might have a lever to open up to outside air.
EDIT: o.k., maybe your wording is just a bit confusing. They use outside air on the condenser, but it is not "pulled in" to the inside room.
Does A Window Air Conditioner Pull Air From Outside? - HVAC BOSS
The first time you switch on that air conditioner in the summer, it really does seem like magic. Especially if you've had to go without it for any length of
hvac-boss.com
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Those 70's window a/c units were like refrigerators. Must have used a ton of electricity but as a kid in the 70's it was like living in a refrigerator.
That old 70’s era 220VAC 25,000btu window AC my father had definitely met the bill and honestly our electric bill was far lower than the neighbors with an “efficient “ whole house unit.
It was never cleaned, never got moldy and you could fill a swimming pool with the runoff of water out the back
They would run the furnace fan to circulate the cooled air.
They do plan to run the furnace fan to circulate the air.
I am thoroughly confused (which is not uncommon).You're kind of stating that both occur: pull air in from the outside AND recirculate the interior air?? Modern window units do not pull air from the outside, except as noted that a few might have a lever to open up to outside air.
EDIT: o.k., maybe your wording is just a bit confusing. They use outside air on the condenser, but it is not "pulled in" to the inside room.
Does A Window Air Conditioner Pull Air From Outside? - HVAC BOSS
The first time you switch on that air conditioner in the summer, it really does seem like magic. Especially if you've had to go without it for any length of
@bullwinkle, are you saying that outside air is drawn in and through the evaporator where it is cooled (causing the moisture in the now-cooled air to drop out, thus the drip of condensate from the evaporator)?
What then happens to the cooled air? If it is not blown into the living space, it must be exhausted to back outside.
How does the inside living space get cooled then? Does the cooled outside air then pass through a heat changer to cool the inside air (which is brought in by the same fan)?
The inside air, when cooled, would also release precipitate, which would have to be released to the outside.
I need to do some research!
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Left side: I have little to no restrictions and able to move huge volumes of air over the coils with a fan no larger than the heart of an artichoke
Right: I have a merv16 filter that is 8” thick and pleated. I need a ECM motor the size of a medium snowblower and costs a couple thousand if it breaks
Bad Idea! You are right. Get a free estimate to repair the existing unit or get a new window unit. Depending on local electricity costs, one may save money to buy a 15/16 seer. Your friend needs to shop various electricity sellers for lower KW pricing. .02
