Rheem 511161 Owner's Manual And Installation Instructions page 51

SOLAR CONTROLLER OPERATION AT START-UP
When the electrical supply is switched on to the solar control unit at start-up:

If there is no solar gain, the circulator will not activate and the green LED will emit a slow pulse.
The slow pulse indicates the circulator is not activated and the power to the solar control unit has been on
for less than 48 hours.

If there is solar gain, the circulator activates and the green LED will emit a series of three (3) flashes.
The three (3) flashes indicate the circulator is operating and power to the solar control unit has been on
for less than 48 hours.
The circulator will operate at full speed for approximately fifteen (15) seconds.

After fifteen (15) seconds, the solar controller will commence to pulse the circulator to reduce the flow
rate through the collector circuit. This will increase the temperature rise across the solar collector(s)
and assist in maximising the system efficiency for the available solar energy. It is normal operation
for the circulator to experience a pulsing effect.

The red LED may emit a rapid pulse for a short period (whilst the green LED is emitting a series of three (3)
flashes), particularly if the solar collector(s) were left uncovered during the final stages of the installation
and commissioning procedure.
This indicates a temperature difference between the hot sensor and cold sensor of greater than 45°C and
does not represent a fault code. This is the result of a build-up of heat and increase in water temperature
in the solar collector(s) prior to the switching on of the electrical supply to the solar control unit.
The rapid pulsing of the red LED will cease as the water circulates and the heat is dissipated from the
solar collector(s). This should be within four (4) to five (5) minutes of start-up, but may take up to ten (10)
minutes.
Whilst the red LED is emitting a rapid pulse, the circulator will operate at full speed. After the red LED has
extinguished, the solar controller will commence to pulse the circulator to reduce the flow rate through the
collector circuit.
If the red LED does continue to emit a rapid pulse for longer than ten (10) minutes, this may indicate water
is not circulating through the solar collector(s) and collector circuit:
switch off the electrical supply at the power outlet to the solar control unit

repeat the procedure to bleed the solar collector(s)

switch on the electrical supply at the power outlet to the solar control unit.

51
COMMISSIONING