28 – Part 3: Solar water heater system installation – Commissioning the solar system
Commissioning the solar system
Prior to fi lling the solar collectors with heat transfer fl uid, ensure that the collectors have been covered for a minimum of 1
hour. The solar loop piping should be pressure tested with air (40 psi) and checked for leaks before you pressurize the solar
collector loop with glycol. The charging process will require a low fl ow high head end suction pump to fi ll and pressurize the
collector loop.
1. Mix the propylene glycol and distilled water in accordance with the propylene glycol Data Sheet in the back of this manual.
Two collector systems will require approximately 6 gallons of fl uid; three collector systems will require approximately 7.5
gallons of fl uid. Connect the discharge side of the end suction fi ll pump to the fi ll valve (1). Place the pump suction side
hose in the propylene glycol solution. Close the pump station controller ball valve (2). Connect a hose to the drain valve (3)
and place the other end of the hose in the empty bucket. Prime the end suction pump.
2. Open the fi ll and drain valves. Turn the “hot ”(4) and “cold” (5) line isolation valves 45 degrees. Turn on the end suction
pump to begin charging the collector loop with glycol. Run the pump 15-20 minutes to purge air from the system while
periodically opening and closing the ball valve (2).
3. With the pump running and while watching the system pressure gauge (6), adjust the fi ll valve (1) to the almost closed
position. Close the drain valve (3) and allow the system pressure to slowly build up to 50 psi -- immediately close the fi ll
valve (1) and then turn off the pump.
4. Remove the fi ll hoses from the pump station controller and install the fi ll valve and drain valve caps.
5. Turn power on to the pump station. The pump station controller is factory preset for solar systems with electric backup
or solar preheat systems. When used with boiler backup the controller program must be modifi ed.
6. Fully open “hot ”(4) and “cold” (5) line isolation valves and the pump station controller ball valve (2)
7. Bleed air from the pump (7)
6
1
4
5
7
3
2