HTP PH130-119S, Installation Operation & Maintenance

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I.CHARGING THE SYSTEM
Closed Loop Glycol
Solar Tank
Fill the solar tank with water. Do this by opening the cold water isolation ball valve to the solar tank.
Inspect all fittings for leaks. The solar collector loop should be pressure tested with air (25 lbs.) before you
pressurize the solar collector loop with glycol. Mix the DowFrost propylene glycol and distilled water in
accordance with the data sheet in the back of the manual. The charging process will require a low flow
diaphragm pump to fill and pressurize the collector loop.
Solar Collector
Connect the discharge side of the pressure pump to the fill valve. 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. One Collector System 3.5 gallons
2. Two Collector System 4.5 gallons
*Assumes a total 100’ pipe run using ¾” Type M hard copper tubing.
The solar heat exchanger has a 1.5 gallon fluid capacity.
Open the upper fill valve (#18) and allow the pressure from the expansion tank to push the water in the
glycol loop back to prime the pressure pump. When the hose in the bucket containing the glycol mixture
stops bubbling, you may begin charging the collector loop with glycol. With both fill and drain valves open,
run the low flow diaphragm pump until the glycol mixture 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 (generally in the range of 25 psi). To more accurately calculate the
proper pressure, measure the height of the solar collector above the tank and divide this number by 2.31,
then add 20 psi to this number.
The pressure in the glycol loop should not exceed 45 psi when the system is in operation on a sunny day.
Contact your solar contractor if the collector loop exceeds the threshold.
After pressurizing the solar system, run the circulator and allow the air to purge out of the vent. Once
purged, monitor pressures and check for leaks before insulating pipes. Pressure should then be about 25
psi.
Above ground 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’ and the piping supports must not
crimp or compress the insulation.
J. COMMISSIONING THE SYSTEM
Closed Loop Glycol
After the glycol 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, you may have to activate the circulator pump. Once the