Solving Problems Based On Symptoms; Symptom: The Unit Is Not Heating Or Cooling As Expected; Symptom: The Compressor Does Not Start (Space Heating Or Domestic Water Heating); Symptom: The Pump Is Making Noise (Cavitation) - Daikin Altherma Installer's Reference Manual

12 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 or
cooling as expected
Possible causes
The temperature setting is NOT
correct
The water flow is too low
The water volume in the
installation is too low
Installer reference guide
72
Corrective action
Check the temperature setting on
the remote controller. Refer to
the operation manual.
Check and make sure that:
▪ All shut-off valves of the water
circuit are completely open.
▪ The water filter is clean. Clean
if necessary.
▪ There is no air in the system.
Purge air if necessary. You
can purge air manually (see
"9.3.1 To perform a manual air
purge" on page 68) or use the
automatic air purge function
(see "9.3.2 To perform an
automatic air purge" on
page 69).
▪ 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 "15.11 ESP curve"
on page 104).
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.
Make sure that the water volume
in the installation is above the
minimum required value (see
"6.3.3 To check the water
volume" on page 24).
12.3.2 Symptom: The compressor does NOT
start (space heating or domestic water
heating)
Possible causes
The unit must start up out of its
operation range (the water
temperature is too low)
The preferential kWh rate power
supply settings and electrical
connections do NOT match
The preferential kWh rate signal
was sent by the electricity
company
12.3.3 Symptom: The pump is making noise
(cavitation)
Possible causes
There is air in the system
The water pressure at the pump
inlet is too low
12.3.4

Symptom: The pressure relief valve opens

Possible causes
The expansion vessel is broken
The water volume in the
installation is too high
Corrective action
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
backup heater is correctly
wired.
▪ The backup heater thermal
protector is NOT activated.
▪ The backup heater contactors
are NOT broken.
If the problem persists after you
have conducted all of the above
checks, contact your dealer.
This should match with the
connections as explained in
"6.4.1 About preparing electrical
wiring" on page 25 and "7.6.4 To
connect the main power supply"
on page 37.
Wait for the power to return (2
hours max.).
Corrective action
Purge air manually (see
"9.3.1 To perform a manual air
purge" on page 68) or use the
automatic air purge function (see
"9.3.2 To perform an automatic
air purge" on page 69).
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 "6.3.4 Changing the pre-
pressure of the expansion
vessel" on page 25).
Corrective action
Replace the expansion vessel.
Make sure that the water volume
in the installation is below the
maximum allowed value (see
"6.3.3 To check the water
volume" on page 24 and
"6.3.4 Changing the pre-pressure
of the expansion vessel" on
page 25).
ERLQ004~008CAV3 + EHBH/X04+08CA
Daikin Altherma - Low Temperature Split
4P313774-1C – 2012.11
the