HTP PH130-119S, Installation Operation & Maintenance

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Depending on the controller model, the differential controller uses 10k ohm thermistors or 1k RTDs to
monitor the temperature difference between the collector and the solar water heater. The controller turns
on when the collector is 12-20
o
F above tank temperature and turns off when the differential drops to 4
o
F.
H. GENERAL SOLAR PANEL ORIENTATION
Part of the performance of your solar water heater is based on the correct orientation of the solar panels.
The collector should be mounted as close to the storage tank as possible to minimize heat loss in the
piping runs. In North America,
collectors should be oriented
facing due south. However, if
this is not possible, they may
be installed within 40 – 60
degrees of due south. Optimal
tilt is +/- 10
o
from the latitude of
the site. The solar collector
must be located in an area of
the roof that will be unshaded
for the majority of the day (from
9 AM – 3 P<) year round.
Adjacent buildings and trees
should be checked for possible
winter shading.
You must consult your solar
panel installation manual for
recommended mounting and
positioning of the panels.
I. GENERAL SOLAR PANEL INSTALLATION
The contractor shall obtain all required permits and approvals for installing the solar system. The
installation shall conform to all federal, state and local regulations governing solar water heating system
installations. 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. Before the installation, the contractor shall inspect the condition of the roof and
notify the homeowner of any existing roof damage or necessary repairs. The most important structural
consideration is to securely anchor the solar collector and the solar strut mounting hardware to the
structural members of the roof with stainless steel hanger or lag bolts as detailed in figures below.
Consult with the panel manufacturer installation manual for proper guidelines in your application.
Preserving the integrity of the roof membrane is the most important roofing consideration. Ensure that all
roof penetrations required to plumb and mount the solar collector are properly flashed and sealed in
accordance with standard roofing practices. The recommended elastomer for sealing roof penetrations is
Tremco “POLYroof”.
Figure 2 – Example of Solar Panel Orientation – LP-199-O