Rheem 052303 Solar Monitor LED

A solar monitor is located in the side of the solar control unit and houses both a green and a red LED.  Differential controllers also have duplicate green and red LEDs on the circuit board).

The green LED (marked ‘SOLAR’) indicates the current operational mode of the solar controller and will emit either a constant glow (on solid), constant pulsing or a series of flashes.

The red LED (marked ‘ATTENTION’) is used to indicate a fault mode and will emit a series of flashes if a fault condition is detected.

(1) If the system is in standby mode (green LED will be on solid or emitting a slow pulse) and the solar storage cylinder is full of hot water, the red LED may simultaneously remain on solid if solar radiation is still being received by the solar collectors. This does not indicate a fault. The red LED will extinguish when the temperature in the solar collectors falls below 130°C.

(2) During periods of high solar radiation when the circulator activates after having been off (green LED will begin emitting a rapid pulse or a series of 3 flashes), it is possible for the red LED to simultaneously emit a rapid pulse for a period of up to ten (10) minutes. This does not indicate a fault. This is normal operation and the red led will extinguish when the temperature difference between the hot and cold sensors decreases due to circulator operation.