Rheem GAS BOOSTED SOLAR WATER HEATER - Manual (Page 41)

COMMISSIONING
41
Drain Back Function
13. Switch off the electrical supply at the power outlet to the solar storage tank.
The pump will deactivate.
The closed circuit fluid will drain back down to the heat exchanger and the level of the closed circuit
fluid in the clear hose will rise.
Wait five (5) minutes to allow the drain back of the closed circuit fluid in the solar circuit.
14. Note the level of the closed circuit fluid in the fluid level hose.
The closed circuit fluid should drain back to the original static level.
If the closed circuit fluid does not drain back completely to this level, then check:
ƒ there is a continuous fall of at least 5 ° (1 in 10 grade) in the solar pipe work from the solar
collectors to the solar storage tank.
ƒ the solar collectors have an inclination of not less than 10°.
(refer to “Solar Collector Location” on page 26)
ƒ the connectors on the inlet and outlet of the collectors are orientated downwards to ensure
complete drain back of the closed circuit fluid from the solar collectors.
If necessary, rectify the:
ƒ solar pipe work if there is either insufficient fall or not a continuous fall in the pipe work.
ƒ solar collector inclination if it is less than 10°.
ƒ orientation of the connectors downwards if they are not orientated correctly.
Recheck the drain back function of the solar circuit by repeating step 7 and recommencing this
procedure from step 9.