SolarAttic PCS1, User Manual

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SECTION 2 - HEATING DATA Page S2-6
and the pool. This is the attic temperature minus the swimming pool temperature.
Then, simply draw a horizontal line to the left scale from the curve and read the
output rise in
°
F. An example of a 32
°
F temperature differential is an attic at 110
°
F
and a swimming pool at 78
°
F.
Observe that as flow rate decreases for a given and constant temperature
differential that the output in
°
F will increase. Conversely, as flow rate increases,
output temperature in
°
F will decrease. The amount of heat transfer, however, is
the same in both instances as long as the temperature differential remains constant
and is governed by the formula BTUS = 500 x
D
T x GPM . The constant 500 is
derived from the weight of water at 8.34 pounds per gallon times the factor 60 used
to convert the heat transfer to an hourly rate.
Observe also that as the temperature differential increases between the attic
and the pool, that the rate of heat transfer also increases. The attic temperature
should be measured inside the attic at or near its peak. Once operating, the PCS1
will stratify the attic with lower temperatures at the attic floor and higher
temperatures at its peak. The PCS1 will simply take the solar radiation off the inside
of the roof at the same time it emanates into the attic. The roof will function as a
massive solar panel!