Would You Heat a Room With a Heat Grabber?

| 10/2/2009 1:54:57 PM

Tags: question to readers, heat grabber,

Heat GrabberMost of us prefer to heat and cool our houses or apartments with simple-to-use machinery such as furnaces and air conditioners. The next level of difficulty in heating might be the use of a woodstove for heat, or opening and closing windows for cooling. But you can go one step further and build a heat grabber.

A heat grabber is a simple box, painted black, that hangs outside of a south-facing window. The box is hollow and insulated. The sun strikes the black flat face, heats the air inside the box and the hot air flows naturally up and into the room. Some folks add a small fan to the unit to move the air further into the room, but it can be used effectively in a small room even if you don’t use a fan.

So, would you be willing to build and use a heat-grabber box to heat a cold room in your house? If so (or not), tell us about it in the comments section below.

3/25/2010 11:49:28 PM

I built a similar design last fall. I ligned the inside of the box with soda and beer cans painted with flat black bbq paint. The whole box is approx 3ft wide by 5ft high. I used insolated 4 in dryer duct to vent it into the house. On sunny days when the temps are above 20 which is most winter days I can top out at 110deg. If its over 30 out i can get 120+deg air. The front is plexi with a slight bow design. The cans give the heater a larger serface area whiches increases heat out put. I plan on making a few more as this 1 heater saved 100 gal of oil this year compared to last. E mail me for pict and more info. Kingbumbles22@yahoo.com

3/15/2010 4:02:37 PM

Absolutely! We live in Maine, and unfortunately our old house only has two small windows on our south facing wall. I've been thinking about this project over for about three years. I'm hesitant about cutting holes in the house for a wall mounted unit, so I'm going to make a window heat grabber first.

1/8/2010 10:02:05 PM

I built this heat collector in Sept. 09, installed it Oct 1st,then enjoyed only 6 days of sun in Oct. (Chicago area) Those 6 days produced great heat. Days of sunlight are less than I expected. It is now Jan 8th, 2010 and since Dec 20 or so we've had 4 good days of sun. I sure hope this year is unusual. Last week I measured 94 degrees input air, while outside temp was 20 or so. I have the duct work stopping at our inside double hung window so we can close the window when it is not producing - a must - it is cool when not sunny and at night. I want to build two more for south facing windows, one more this winter still. Thanks MEN, keep up the good work.

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