17
• If the space heating system requires water temperatures
in excess of 120°F, a tempering valve (provided) must
be installed per the manufacturer’s instructions in the
potable hot water supply to limit the risk of scald injury.
• Pumps, valves, piping and fi ttings must be compatible
with potable water.
• A properly installed fl ow control valve is required to pre-
vent thermosiphoning. Thermosiphoning is the result
of a continuous fl ow of water through the air handler
circuit during the off cycle. Weeping (blow off) of the
temperature and pressure relief valve (T & P) or higher
than normal water temperatures are the fi rst signs of
thermosiphoning.
• The hot water line from the water heater should be
vertical past any tempering valve or supply line to
the heating system to remove air bubbles from the
system.
• Do not connect the water heater to any system or
components previously used with non-potable water
heating appliances when used to supply potable water.
Storage Tank Installation
When installing the Polaris® with a storage tank, see figure
18 for piping suggestions.
Solar Installation
If this water heater is used as a solar storage heater or as
a backup for the solar system, the water supply tempera-
tures to the water heater tank may be in excess of 120°F.
A tempering valve must be installed in the water supply
line to limit the supply temperature to 120°F.
Note: Solar water heating systems can often supply water
with temperatures exceeding 180°F and may result in
water heater malfunction.
Figure 17: Air Handler Piping Installation
Massachusetts code does not
allow this type of installation.
*100 Gallon Model Shown.