Installation manual
26
RKHBH/X016AB
Indoor unit for air to water heat pump system
4PW50205-1A
T
ROUBLESHOOTING
This section provides useful information for diagnosing and
correcting certain troubles which may occur in the unit.
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.
Before contacting your local dealer, read this chapter carefully, it will
save you time and money.
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!
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)
Symptom 4: The water pressure relief valve opens
Symptom 5: The water pressure relief valve leaks
Symptom 6: The user interface displays "
n
n
n
n
" when pressing
certain buttons
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.
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 >0.3 bar
(water is cold), >>0.3 bar (water is
hot).
• 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 "Setting the pump
speed" on page 17).
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 "Checking
the water volume and expansion
vessel pre-pressure" on page 10).
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 14. 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 >0.3 bar
(water is cold), >>0.3 bar (water is
hot).
• 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 "Setting the pre-
pressure of the expansion vessel" on
page 10).
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
The expansion vessel is broken.
Replace the expansion vessel.
The water volume in the installation
is too high.
Make sure that the water volume in
the installation is under the
maximum allowed value (refer to
"Checking the water volume and
expansion vessel pre-pressure" on
page 10).
P
OSSIBLE
CAUSES
C
ORRECTIVE
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.
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
The current permission level is set to
a level that prevents using the
pressed button.
Change the "user permission level"
field setting ([0-00], see "Field
settings" on page 18.
1D_IM_4PW50205-1A.book Page 26 Thursday, January 29, 2009 12:00 PM
