EKHBH/X008BB
Indoor unit for air to water heat pump system
4PW62570-1A – 01.2011
Installation manual
46
11. T
ROUBLESHOOTING
This section provides useful information for diagnosing and
correcting certain troubles which may occur in the unit.
This troubleshooting and related corrective actions may only be
carried out by your installer.
11.1. General guidelines
Before starting the troubleshooting procedure, carry out a thorough
visual inspection of the unit and look for obvious defects such as
loose connections or defective wiring.
When a safety device was activated, stop the unit and find out why
the safety device was activated before resetting it. Under no
circumstances safety devices may 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!
11.2. General symptoms
Symptom 1: The unit is turned on (
y
LED is lit) but the unit is
not heating or cooling as expected
Symptom 2: The unit is turned on but the compressor is not
starting (space heating or domestic water heating)
Symptom 3: Pump is making noise (cavitation)
INFORMATION
Refer to the service manual to carry out any service mode
operation.
DANGER
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.
DANGER: ELECTRIC SHOCK
See
"2. General safety precautions" on page 2
WARNING
In order to avoid a hazard due to inadvertent resetting of
the thermal cut-out, this appliance must not be supplied
through an external switching device, such as a timer, or
connected to a circuit that is regularly switched on and off
by the utility.
DANGER: DO NOT TOUCH PIPING AND INTERNAL
PARTS
■
Do not touch water pipes during and immediately after
operation as the pipes may be hot.
■
Do not touch the refrigerant pipes during and
immediately after operation as the refrigerant pipes
may be hot or cold, depending on the condition of the
refrigerant flowing through the refrigerant piping,
compressor, and other refrigerant cycle parts.
■
Do not touch the internal parts (pump, backup heater,
etc.) during and immediately after operation.
See
"2. General safety precautions" on page 2
INFORMATION
For problems related to the optional solar kit for domestic
water heating, refer to the troubleshooting in the
installation manual of that kit.
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
The temperature setting is not
correct.
Check the controller set point.
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)
• Check that the pump speed
setting is on the highest speed.
• Make sure that the expansion
vessel is not broken.
• Check that the resistance in the
water circuit is not too high for the
pump (refer to
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
the water volume and expansion
vessel pre-pressure" on page 16
).
P
OSSIBLE
CAUSES
C
ORRECTIVE
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 (15°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.
The benefit kWh rate power supply
settings and electrical connections
do not match.
If [d-01]=1 or 2, the wiring requires
specific installation like illustrated in
"Connection to a benefit kWh rate
power supply" on page 22
. Other
correctly installed configurations are
possible, but are to be specific for
the type of benefit kWh rate power
supply type at this specific site.
The benefit kWh rate signal was sent
by the electricity company.
Wait for the power to return.
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
There is air in the system.
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