Solar air heater modification update Dec 09

This heater has aluminum cans inside the downspouts with the bottoms cut out and the tops left on but tabs removed. I thought I should mention that . I modified blower mounting and ducting to use just one high volumn blower for both panels. This was an after thought or I would have cut the top hole in another spot for better air flow thru the tubes. I still need to tidy up the wiring after I have everything working the way I want. I also am only using one snap disk for both panels. So you can save a little money on that and by having only one blower. My temperature keeps up ok with the high air flow. on the hottest part of the day I get about 115 degrees out of them at the wall outlet. as the sun gets weaker that gradually decreases. It has run as long as 5 hrs steady. This time of the year the days are short so I am expecting longer running times. I really think having to much air flow is better than not enough. The worst that can happen is the blower will run intermittenly if the heat can't keep up. More volumn of air gives you more heat flow thru the rest of the house. I didn't show it but I also have one of those small doorway fans moving air from this room into the living room. I have that plugged into the extension from the snap disk down by the blower so It starts when the main blower does. When the sun is out strongest I can shut off my furnace and the panels keep the temp at 72 degrees in the living room. Outside temps last week were down to 5 degrees outside and I still got heat out of the panels for a few hours when the sun was out. Might still add another panel horizontal below the 2 I have now. I have 2 of the soda can heaters on my garage also. Same size boxes as the ones on the house. My house is only around 1000 sq ft. and I have it insulated pretty well. I have 1 inch rigid foam outside under the siding. I have a ton of windows but they are all Anderson windows I put in several years ago. I'm pretty happy with the solar heater so far. In case anyone is interested Grainger has the snap disks for about $11. I also just bought 3 used attic fans that have the adjustable heat settings on them. Might try them on another panel but they are 12 in in diameter but only 1800 RPM. was thinking about maybe making bigger inlet and outlet on one.

Category:

Science & Technology

Tags:

• Solar
• Solar heater
• pop can solar heater
• downspout solar heater

[Tri3Dr]

How 'bout making intake which is closer to the blower, smaller? It would cause more air to go through second intake.

Right size would be found by doing some experiments. :)

[wiboater4]

@Tri3Dr Since the time I did this video I switched to a 12 volt car heater blower that I run off of my solar battery bank. It blows more air than the one in the video. now both panels are putting about the same amount of air thru. The car heater blower had 2 small blowers run by a center motor. I don't know the RPM for it.

[wiboater4]

You probably were getting some solar heat thru the windows anyway. It would be good to leave the sun come through them and put the boxes alongside them. you could make something to bring the duct thru at the bottom of the window or top. I thought I would have to cover mine for summer but they don't seem to be a problem. I just unplug the power to the blower on them.

[wiboater4]

I am getting a lot more running time on these now that the sun is out longer. They are working well. I'm starting to think about ways to cover them over for summer to prevent them from getting to hot. I might make a removable water tube setup to heat water for summer.

[water4fuelh20]

Nicely done. Have you thought about just adding another fan to you second panel rather than using just one fan to even out the air flow, Pressure differences between the 2 panels will also have an effect on air flow as well. Keep up the good work.

[wiboater4]

I started with 2 fans and went to just the one. I have plenty of airflow with one. I figure I use less electricity this way. Only thing I'd do different is mount it midway between the 2 and add a few baffles.

[sc00b3rt]

These are great, if the sun is out of course. WE actually used our south facing windows and put ours inside those (used the foam insulation to make the box). So in the Summer months we simply take them out of the windows.

[sc00b3rt]

These are great, if the sun is out of course. 

[a1boywonder]

i have a 2 ft x 4 ft one on my house and it runs about 6 hours a day in mid jan.. but i live in tenn.the blower i got from home depot and only cost $2 per winter to run CHECK IT OUT ON MY CHANEL-every thing but the snap disc i got at home depot .

[STARFIRESOLAR]

Today at 11 am my output temp was about 135 or so. The reason you are experiencing more heat with the tops on the cans is because there is more metal that is being heated and therefore more heat exchange area that the air touches. The sun heats the exposed metal and heat radiates from them. However radiant heat doesn't heat air very good, it heats metal or other objects. Direct contact with the metal heats the air. The tops provide more metal that is heated for metal to air heat exchange.