Velux CLI U12 SD0W118 El B/U Installation Operation & Maintenance page 13

5. Other system components:
a. Anti-Scald Mixing Valve: Automatically
blends the hot water and the cold water feed
line to control the discharge temperature to
an acceptable and safe temperature. This will
also increase the amount of hot water that
is drawn from the solar storage tank by not
allowing the incoming water to fully temper
the hot water stored inside the tank.
b. Expansion tank: Pre-charged with air to allow
for the expansion as the heat transfer fluid
expands and contracts with heating and
cooling.
c. Solar collector temperature sensor
This sensor is wired to the solar controller
and automatically turns on the circulator
pump when the differential set point is
reached between the solar water heater and
the solar collector.
d. Tank temperature sensor: The tank sensor
is wired to the solar controller to measure
the temperature on the bottom of the solar
storage tank.
e. VELUX flexible piping: Pre-insulated
corrugated stainless steel flexible piping
designed specifically for VELUX solar loop
piping. VELUX has designed a special cone
shaped fitting which ensures a tight and
secure connection to collectors without
requiring a gasket or o-ring seal.
f. Microbubble air separator: This automatic
air vent is used in the solar system to allow
air contained in the system to be released.
The air vent valve is designed to work in
high temperatures( as high as 350°F) with a
propylene glycol medium.
g. Propylene glycol heat transfer fluid: Non-
toxic fluid used to transfer heat from solar
collectors to solar storage tank. Includes
corrosion inhibitors to prevent corrosion of
solar loop components.
Expansion tank
Tank temperature sensor
Microbubble air separator
Part 3: Solar water heater system installation – 13
Anti-Scald Mixing Valve
Collector temperature sensor
VELUX flexible piping
Propylene glycol