State Standard Systems - Manual (Page 13)

13
Figure 10.
collector location
Proper location and orientation of the solar collectors is
important for maximum system efficiency. The collectors
should be unshaded from 10:00 am through 3:00 pm each
day in every month of the year and should be located as
close to the storage tank as possible to minimize heat loss
in the piping runs. The best orientation is achieved when
the collectors are facing due south +/- 45° and tilted at
an angle from the horizontal equal to the latitude of the
solar collector installation
location + 15°. A steeper angle provides better winter per-
formance as the sun is lower in the sky. The collectors
will also shed snow more effectively at the steeper angle.
Figure 10 below shows many alternatives for collector
mounting. Placing the collectors as close as possible to
the peak of the roof will make installation easier by provid-
ing increased attic access.
General considerations
The contractor shall obtain all required permits and
approvals.
The installation shall conform to all federal, state and local
regulations, codes, ordinances and standards governing
solar water heating system installations and the contractor
shall adhere to sound building safety and trade practices.
Special consideration must be given to building code
requirements for the penetration of structural members
and fire rated assemblies.
ensure the mounting surface is solid and able to with-
stand in excess of 330lbs / 150kg of pull force that
may be encountered during high winds. consult a
structural engineer if in doubt.
The solar collector must be located in a structurally sound
area of the roof that will be unshaded for the majority of the
day all year round. Adjacent buildings and trees should be
checked for possible winter shading. An instrument such
as the Solar Pathfinder (www.solarpathfinder.com) can be
used for solar site analysis.
Before the installation the contractor shall inspect the con-
dition of the roof and notify the homeowner of any existing
roof damage or necessary repairs.
collector orientation
Proper tilt angle for solar collectors is latitude plus 15°.
This 15° additional tilt improves performance in the
winter, when the sun is weaker and at a lower angle.
The cost in performance in the summer when the sun is
high is overcome by the hours of sunlight and strength
of irradiation that occurs in the summer. Tilt mounting
accessory kits are available to set the proper collector
angle. Please call your local dealer for more information.
When the collectors are mounted one behind the other,
they should be spaced sufficiently apart so that when the
sun is at its lowest altitude, the collectors will not shade
each other and cause efficiency loss. See Figure 11 and
Table 3. If a collector must be installed horizontally, replace
the upper vent with a rubber plug in order to prevent rain
penetration. See Figures 12 & 13.