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13.2 General symptoms
Symptom 1: The unit is turned on but the unit is not heating or
cooling as expected
When a safety device was activated, stop the unit and find out why
the safety device was activated before resetting it. Under no
circumstances can safety devices be bridged or changed to a
value other than the factory setting. If the cause of the problem
cannot be found, call your local dealer.
If the pressure relief valve is not working correctly and is to be
replaced, always reconnect the flexible hose attached to the
pressure relief valve to avoid water dripping out of the unit!
For problems related to the optional solar kit for domestic
water heating, refer to the troubleshooting in the Installation &
Owner's manual for that kit.
When carrying out an inspection on the switch box of the
unit, always make sure that the main switch of the unit is
switched off.
POSSIBLE CAUSES
CORRECTIVE ACTION
The temperature setting
is not correct.
Check the controller set point.T4HMAX,
T4HMIN in heat mode.T4CMAX,T4CMIN
in cool mode.T4DHWMAX,T4DHWMIN
in DHW mode.
Symptom 2: The unit is turned on but the compressor is not
starting (space heating or domestic water heating)
POSSIBLE CAUSES
CORRECTIVE ACTION
The unit must start up
out of its operation range
(the water temperature
is too low).
In case of low water temperature, the
system utilizes the backup heater to
reach the minimum water temperature
first (12°C).
• Check that the backup heater
power supply is correct.
• Check that the backup heater
thermal fuse is closed.
• Check that the backup heater
thermal protector is not activated.
• Check that the backup heater
contactors are not broken.
Symptom 6: Space heating capacity shortage at low outdoor
temperatures
POSSIBLE CAUSES
CORRECTIVE ACTION
Backup heater operation
is not activated.
Controls parts for backup
heater(IBH) ”
Too much heat pump
capacity is used for
heating domestic hot
water (applies only to
installations with a
domestic hot water tank).
Symptom 5: The water pressure relief valve leaks
POSSIBLE CAUSES
CORRECTIVE ACTION
Dirt is blocking the water
pressure relief valve
outlet.
Check for correct operation of the
pressure relief valve by turning the
red knob on the valve counter
clockWise:
• If you do not hear a clacking sound,
contact your local dealer.
• In case the water keeps running out
of the unit, close both the water inlet
and outlet shut-off valves first and
then contact your local dealer.
The water flow is too
low.
• Check that all shut off valves of the
water circuit are completely open.
• Check if the water filter needs cleaning.
• Make sure there is no air in the system
(purge air).
• Check on the manometer that there is
sufficient water pressure. The water
pressure must be>1 bar (water is cold).
• Make sure that the expansion vessel
is not broken.
• Check that the resistance in the water
circuit is not too high for the pump
POSSIBLE CAUSES
CORRECTIVE ACTION
The expansion vessel is
broken.
Replace the expansion vessel.
The filling water pressure
in the installation is
higher than 0.3MPa.
Make sure that the filling water pressure
in the installation is about
0.15~0.20MPa (refer to "
9.3 water
pipework/Checking the water volume
and expansion vessel pre-pressure
").
Symptom 3: Pump is making noise (cavitation)
POSSIBLE CAUSES
CORRECTIVE ACTION
Purge air.
Water pressure at pump
inlet is too low.
• Check on the manometer that there
is sufficient water pressure. The water
pressure must be > 1 bar (water is
cold).
• Check that the manometer is not
broken.
• Check that the expansion vessel is
not broken.
• Check that the setting of the
pre- pressure of the expansion
vessel is correct (refer to "
9.3 water
pipework/Checking the water volume
and expansion vessel pre-pressure
").
Symptom 4: The water pressure relief valve opens
The water volume in the
installation is too low.
Make sure that the water volume in the
installation is above the minimum
required value (refer to "
9.3 water
pipework/Checking the water volume
and expansion vessel pre-pressure
").
WARNING
NOTE
50
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