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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
with the system.
The modes are:
Flashes
Operational 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
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 to the heat pump 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 off
compressor fault condition
3 x red
Heating unit on
compressor cooling fault condition
4 x red
Heating unit on
tank thermistor fault condition
5 x red
Heating unit on
evaporator thermistor fault condition
6 x red
Heating unit on
compressor thermistor fault condition
9 x red
Heating unit on
compressor fault condition
Notes:
Power must be available at the water heater and to the heat pump for the LEDs to glow or flash.
There are no 7 or 8 x red flash fault mode codes.
When power is turned on or reconnected to the water heater, the red LED will emit a solid glow for
three (3) seconds and then extinguish. This is normal operation and does not indicate a fault. The LED
display will then return to the current operational status.
If there is power to the water heater and the green LED is off or the red LED is flashing, this indicates
there may be a fault condition with the water heater. The red LED may emit up to nine flashes in each
series of flashes. Refer to
“Possible fault condition”
on page 41.
Time controlled power supply (power must be available at the water heater)
If the water heater is connected to a time controlled power supply, then during periods of no power
supply at the water heater the LEDs will be off.
This is not a fault condition, but a result of no power being available to energise the LEDs.
The green LED will recommence glowing or flashing when power is available again at the water heater.