TABLE B-2: Flow Rates for Various Copper Tubing Sizes
Flow Rates (gpm)
Generally, storage volume is based only on collector area, and should be between
1.5 and 2.5 gallons per square foot of gross collector area.
Systems with a load which overwhelms the solar system should have storage
volumes at the lower end of the range. Systems which collect more heat than the
load can use per day should have storage volumes in the upper end of the range.
Collectors should be tilted from the horizontal (not from a pitched roof!) according to
the table below. The tilt should be within 10 degrees of the listed angle. For
example, a spaceheating system at a latitude of 35, which should have a tilt of 50,
can have a tilt angle of 40 to 60 without a noticeable decrease in annual