This video shows a new design for the making a DIY Solar Air Heater. This one is made with 7 lengths of 2×2 Steel “Drip Edge” Roof Flashing. Each of the 7 slats are dual-faceted and each create their own air channel. This gives a total of 7 closed air channels (and 6 open ones).via: desertsun02
The basics: the sun enters the unit thru the glass and strikes the 14 individual facets or faces of the absorbent black steel flashing. The metal is then quickly heated, and in turn, this heats the air inside the unit. The hot air is drawn out by using a small solar powered 12vdc case fan (located at the top).Watch the video from desertsun02 for more info:
Note that the units’ fan is only activated in the presence of sunlight so it automatically shuts off when no heating is occurring. By using the 13 individual air inlets the air enters ‘equally distributed’ and is evenly heated as it passes over and under the hot steel slats.
Air temps were in the low 40’s (F) during testing. Output air temps varied but reached into the 160F+ range (topping out at 167.5 F (74C+) about noon time). Lowest temp recorded was 110F (with sun just over horizon) and air temps of 135F were standard for mid-morning and late afternoon. Collector works great!//desertsun02