Daikin EBLQ05+07CAV3 Installer's Reference Manual page 81

Possible causes
The water flow is too low
The water volume in the
installation is too low
EBLQ05+07CAV3 + EDLQ05+07CAV3 + EKCB07CAV3 +
EK2CB07CAV3 + EKMBUHCA3V3 + EKMBUHCA9W1
Daikin Altherma low temperature monobloc
4P405544-1 – 2015.03
Corrective action
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
"To perform a manual air
purge" on page 76) or use the
automatic air purge function
(see "To perform an automatic
air purge" on page 76).
▪ 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 111).
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
and flow rate" on page 27).
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 Troubleshooting
Corrective action
If the system contains a
backup heater:
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 contactors
are NOT broken.
If the system does NOT
contain a backup heater:
It may be required to start up with
a small water volume. To do this,
gradually open the heat emitters.
As a result, the water
temperature will gradually rise.
Monitor the inlet water
temperature ([6.1.6] in the menu
structure) and make sure it does
NOT drop below 15°C.
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 Preparing electrical
wiring" on page 29 and To
connect the main power supply.
Wait for the power to return (2
hours max.).
Corrective action
Purge air manually (see "To
perform a manual air purge" on
page 76) or use the automatic air
purge function (see "To perform
an automatic air purge" on
page 76).
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 28).
Installer reference guide
81