COMMISSIONING
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DIAGNOSTIC FEATURES OF THE HEAT PUMP CONTROLLER
An operating mode monitor is located on the front of the heat pump module and
houses a green and a red LED.
The green LED, marked “NORMAL”, indicates the current operating mode of
the heat pump water heater and the red LED, marked “ATTENTION”, indicates
a fault mode.
The green LED will emit either a constant
glow or a series of flashes, with a 2 second
interval between each series. A series of
long green flashes may also be emitted.
The red LED will emit a series of flashes,
with a 2 second interval between each
series, only if there is a particular fault
condition within the system.
The Operating Modes are:
Flashes
Operating Modes
solid green
(remains on)
Standby mode
– water is hot
1 x green
Call for heating received
– system checks performed
Note: unit may wait and continue flashing until
compressor has cooled from its last operation
2 x green
Circulator commences circulation
3 x green
Heat pump operation
– compressor and fan running
4 x green
Defrost mode
– circulator operates for three (3) minutes
long green
Heating unit on
– ambient air temperature
below 3°C to 5°C or above 45°C to 55°C
no green
(remains off)
No power at the water heater or a possible fault condition
Refer to notes below before calling for service
Flashes
Fault Modes
1 x red
Heating unit on
compressor over temperature
(possible circulator fault)
2 x red
Heating unit on
compressor fault condition
3 x red
Heating unit on
compressor cooling fault condition
4 x red
Heating unit on
lower tank thermistor fault condition
5 x red
Heating unit on
evaporator thermistor fault condition
6 x red
Heating unit on
compressor thermistor fault condition
7 x red
Heating unit on
upper tank thermistor fault condition
