8
Unit switch box
Carry out a thorough visual inspection of the switch box and
look for obvious defects such as loose connections or
defective wiring.
Check for correct operation of contactors K1M, K3M, K5M
(applications with domestic hot water tank only) and K4M by
use of an ohmmeter. All contacts of these contactors must be
in open position.
9
In case of use of glycol
Document the glycol concentration and the pH-value in the
system at least once a year.
A pH-value below 8.0 indicates that a signifcant portion of the
inhibitor has been depleted and that more inhibitor needs to
be added.
When the pH-value is below 7.0 then oxidation of the glycol
occured, the system should be drained and flushed
thoroughly before severe damage occurs.
Make sure that the disposal of the glycol solution is done in
accordance with relevant local and national legislation.
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 carrying out an inspection on the switch box of the
unit, always make sure that the main switch of the unit is
switched off.
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!
R(D/B)LQ011~016AA6V3+W1
Unit for air to water heat pump system
4PW53149-1
General symptoms
Symptom 1: The unit is turned on (y LED is lit) but the unit is not
heating or cooling as expected
P
OSSIBLE CAUSES
The temperature setting is not
correct.
The water flow is too low.
The water volume in the installation
is too low.
Symptom 2: The unit is turned on but the compressor is not starting
(space heating or domestic water heating)
P
OSSIBLE CAUSES
The unit must start up out of its
operation range (the water
temperature is too low).
The benefit kWh rate power supply
settings and electrical connections
do not match.
The benefit kWh rate signal was sent
by the electricity company.
Symptom 3: Pump is making noise (cavitation)
P
OSSIBLE CAUSES
There is air in the system.
Water pressure at pump inlet is too
low.
C
ORRECTIVE ACTION
Check the controller set point.
• 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 20).
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).
C
ORRECTIVE ACTION
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.
If [D-01]=1 or 2, the wiring requires
specific installation like illustrated in
"Connection to a benefit kWh rate
power supply" on page 17. 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.
Wait for the power to return.
C
ORRECTIVE ACTION
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 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 11).
Installation manual
30