I've had a window air conditioner for a while. It seems to only cool the immediate area by the unit, while making a Lot of Noise. Rather annoying, and nearly useless for putting cooling where needed. How could the unit be made quiet, and allow you to get cool air anywhere in the room?

Step 1: Connecting Air Conditioner Blower to Flexible Air Duct

Central air conditioning units blow air through ducts to each room. Maybe this could work with a window unit.

To be honest, I wasn't sure that the window air conditioner could push air through that much duct. Maybe it wouldn't. Maybe the unit would overheat from the extra air resistance. Well, the AC was a thrift store find, about $25, so I didn't mind too much if it got messed up.

I didn't want to put much effort into prototyping a concept which might not have merit, so I used stuff I had around. Cardboard box, tape, etc. The only thing I bought was the flex duct, which is a silver mylar slinky sort of thing. It came in a 20 ft length. It turns out, it works fine with the full length, which can reach anywhere in the room.

At first I had the air conditioner several feet outside the window to moderate noise. But efficiency is lost when the cool air in the tube is warmed by outside air. it's not too loud a few feet from window.

Step 2: Second Iteration: More Professional

The second unit is set up with a tin floor vent, not the cardboard box.

It is still a bit funky since the shortest vent I could find was 10", about 2" too long. but it should last longer than the box, as well as looking better. I also switched to mylar duct tape which is much more suited to ducts.

Step 3: Sealing the Window Around the Duct

Again, this is not a pretty solution, but I was dying in the heat. I just stuffed old pillows around the duct to fill the gap of the open window. Yes, I'll do something better later. For now, it works.

Step 4: Testing Efficiency

Here is an IR Thermometer indicating 41 degrees F. Not bad.

It tends to produce air 20 to 30 degrees cooler than the outside air.

Step 5: Cooling Exactly Where Needed

The flexible duct can be routed anywhere in the room you need it. Since I cope with a condition called erythromelalgia, my feet are often hot. I direct cold air onto them.

Step 6: Rain Protection

Part of the theme of this project is doing it with the least effort. If I made a proper roof over it, I would be working hard, and Not staying Cool. ;)

This floor pad will shed rain away from the electrical bits. The hot side of the unit is meant by the manufacturer to be outside the window, potentially in rain, and the cool side will condense water, even in an ordinary setup.

So a little dampness wont hurt it.

Step 7: Keeping Up Appearances

The contraption works fine. But looks weird. So a piece of camouflage net makes it less obtrusive. Tan net is similar in tone to the brick behind it. The net may also help keep the machine cooler by shading it without completely blocking airflow.



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    6 Discussions


    1 year ago

    Good job thinking outside the box. However the way air conditioners work it to remove heat not produce cold. What is created here is basically bringing ice cubes into a warm room. Which would cool you better; Ice with a fan blowing over it. Once again good job. If it works for you its good. Take pride in solving a problem. :-)

    1 reply

    Reply 1 year ago

    if I set up a system using ice, I could probably go through 10 lb per day. At $2 per 10 lb, that's $60 per month. Much cheaper to run a window air conditioner. See my other instructable about air conditioners for current draw. I will do the math on dollars per month later.


    1 year ago

    could be wrong, but should get insulated ducting to prevent losses.

    1 reply

    Reply 1 year ago

    That would help. I didnt want to deal with fiberglass, but have some silver bubble wrap to use.


    1 year ago