HTP SSU-119SE - Manual (Page 26)

26
LP-199 REV. 4.15.14
For areas with temperatures that fall below
–5 o
C / 23
o
F, a closed loop filled with a polypropylene glycol-water mix should be used to
provide hard freeze prot ection. Please refer to glycol manufacturer’s specifications about the temperature ranges the liquid can
withstand. Only food grade polypropylene-glycol, FDA rated as GRAS, should be used.
NOTE: HTP DOES NOT WARRANT THE SOLAR WATER HEATER, SOLAR COLLECTOR, OR ANY COMPONENTS AGAINST
FREEZE RELATED DAMAGE.
NOTE: The use of glycol not recognized as GRAS is allowed in double wall heat exchanger models ONLY.
PART 8 – START-UP PREPARATION
DO NOT MOVE ON TO THESE STEPS UNTIL THE ENTIRE SOLAR SYSTEM, INCLUDING ALL PIPING, SOLAR COLLECTORS,
SENSORS, PUMP, CONTROLS, AND ELECTRICAL CONNECTIONS, ARE PROPERLY SECURED, INSULATED, LABELED AND
INSTALLED.
A. CHARGING THE SYSTEM
Solar Water Heater
Fill the solar tank with water. Do this by opening the cold water isolation ball valve to the solar tank. See Figs. 6
– 8 for valve locations.
Inspect all fittings for leaks.
Solar Collector
The solar collector loop should be pressure tested with air (25 psi) before you pressurize the loop with HTF. If using glycol, mix in
a
ccordance with the glycol manufacturer’s data sheet. The charging process will require a low flow diaphragm pump to fill and
pressurize the collector loop.
Connect the discharge side of the pressure pump to the fill valve. See Figs. 6
– 8. Place the pump suction side hose in the glycol
solution. Close the ball valve (#11). Connect a second hose to the drain valve (#10) and place the other end of the hose in the empty
bucket.
TOTAL COLLECTOR LOOP FLUID CAPACITY IN GALLONS*
1. Collector System 3.5 gallons
2. Collector System 4.5 gallons
*Assumes a total 100’ pipe run using ¾” Type M hard copper tubing.
The solar water heater heat exchanger has a 1.75 gallon fluid capacity.
Open the upper fill valve (#18) and allow the pressure from the expansion tank to push the water in the loop back to prime the pressure
pump. When the hose in the bucket containing the HTF stops bubbling, you may begin charging the collector loop. With both fill and
drain valves open, run the low flow diaphragm pump until the HTF begins flowing into the empty bucket. Quickly switch the hose from
the empty/return bucket to the bucket containing the glycol mixture. Continue to circulate the fluid using the pressure pump until the
bubbling has stopped and the air has been purged.
After charging the collector loop, shut the lower drain valve (#10) and let the pressure pump drive up the loop pressure to the
appropriate level (in glycol systems, in the range of 25 psi). To more accurately calculate the proper pressure, measure the height of
the solar collector above the solar water heater and divide this number by 2.31. Then add 20 psi to this number.
The pressure in a glycol loop should not exceed 45 PSI when the system is in operation on a sunny day. Contact your solar contractor if
the loop exceeds this threshold.
After pressurizing the solar system, run the circulator and allow the air to purge out of the air vent. Once purged, monitor pressures and
check for leaks before insulating pipes. Pressure should then be about 25 PSI.
Above groun
d piping must be insulated with a wall thickness of at least ¾”. A 1” thickness is required in areas prone to hard freeze
conditions. Above ground insulation must be protected from ultraviolet degradation. All piping must be supported at a maximum interval
of 10 feet and the piping supports must not crimp or compress the insulation.
B. COMMISSIONING THE SYSTEM
After the collector loop has been charged and pressure is around 25 PSI (check gauge on solar heat exchanger) set the solar control to
the desired settings. Solar controls come with default settings that will work in most installations. If it is a cloudy day, the circulator pump
may have to be activated manually. Once the pump is running and the system is fully purged of air, set the control to the desired
settings. It is recommended not to set the storage tank high limit set point any lower than 160
o
F. A lower set point could lower the