Hi all,

I am new to solar heating but have been drawing up some plans to build a forced air unit that is 4 foot X 8 foot X 6 inches deep, and I am wondering what size of a fan should I use(how many cubic feet per minute)? I do not want to force the air through the heater so fast that it doesn't warm up the air sufficiantly but I also would like to get out the optimum amount of heat. any help would be greatly appreciated