12 Troubleshooting
Installer reference guide
65
ERLQ004~008CA + 08S18CB
Daikin Altherma – Low temperature split
4P401676-1 – 2015.02
Before troubleshooting
Carry out a thorough visual inspection of the unit and look for
obvious defects such as loose connections or defective wiring.
12.2
Precautions when troubleshooting
WARNING
▪ When carrying out an inspection on the switch box of
the unit, always make sure that the unit is disconnected
from the mains. Turn off the respective circuit breaker.
▪ When a safety device was activated, stop the unit and
find out why the safety device was activated before
resetting it. NEVER bridge safety devices or change
their values to a value other than the factory default
setting. If you are unable to find the cause of the
problem, call your dealer.
DANGER: RISK OF ELECTROCUTION
WARNING
Prevent hazard due to the 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 turned ON and OFF
by the utility.
DANGER: RISK OF BURNING
12.3
Solving problems based on
symptoms
12.3.1
Symptom: The unit is NOT heating as
expected
Possible causes
Corrective action
The temperature setting is NOT
correct
Check the temperature setting on
the remote controller. Refer to
the operation manual.
The water flow is too low
Check and make sure that:
▪ All shut-off valves of the water
circuit are completely open.
▪ The water filters are clean.
Clean if necessary.
▪ There is no air in the system.
Purge air if necessary. You
can purge air manually (see
"To perform a manual air
purge" on page 60
) or use the
automatic air purge function
(see
"To perform an automatic
air purge" on page 61
).
▪ The water pressure is >1 bar.
▪ The expansion vessel is NOT
broken.
▪ The resistance in the water
circuit is NOT too high for the
pump
(see
"14.9
ESP
curve" on page 95
).
If the problem persists after you
have conducted all of the above
checks, contact your dealer. In
some cases, it is normal that the
unit decides to use a low water
flow.
Possible causes
Corrective action
The water volume in the
installation is too low
Make sure that the water volume
in the installation is above the
minimum required value (see
"6.4.3 To check the water volume
and flow rate" on page 19
).
12.3.2
Symptom: The compressor does NOT
start (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)
If the water temperature is too
low, the unit uses the backup
heater to reach the minimum
water temperature first (15°C).
Check and make sure that:
▪ The power supply to the
backup heater is correctly
wired.
▪ The backup heater thermal
protector is NOT activated.
▪ The backup heater contactor is
NOT broken.
If the problem persists after you
have conducted all of the above
checks, contact your dealer.
The preferential kWh rate power
supply settings and electrical
connections do NOT match
This should match with the
connections as explained in
"6.5 Preparing electrical
wiring" on page 20
and
"7.9.7 To
connect the main power
supply" on page 35
.
The preferential kWh rate signal
was sent by the electricity
company
Wait for the power to return (2
hours max.).
12.3.3
Symptom: The pump is making noise
(cavitation)
Possible causes
Corrective action
There is air in the system
Purge air manually on both
zones (see
"To perform a manual
air purge" on page 60
) or use the
automatic air purge function on
both zones (see
"To perform an
automatic air purge" on page 61
).
The water pressure at the pump
inlet is too low
Check and make sure that:
▪ The water pressure is >1 bar.
▪ The manometer is not broken.
▪ The expansion vessel is NOT
broken.
▪ The pre-pressure setting of the
expansion vessel is correct
(see
"6.4.4 Changing the pre-
pressure of the expansion
vessel" on page 20
).
12.3.4
Symptom: The pressure relief valve opens
Possible causes
Corrective action
The expansion vessel is broken
Replace the expansion vessel.
