Daikin EKOMBG22ABV1 Installation Instructions Manual page 45

No electrical supply (24 V).
8.3.4 The power is reduced
Possible causes:
At high rpm, the power has decreased.
8.3.5 CH is not reaching correct temperature
Possible causes:
Water pressure in installation is too low.
No 
Room thermostat is not set correctly.
No 
Temperature is set too low.
No 
No flow through the installation.
No 
The boiler power is not set correctly.
No 
No heat transfer due to contamination in the CH
boiler/installation.
8.3.6 No domestic hot water
Possible causes:
The service display shows nothing.
No 
The service display shows nothing.
No 
Flow sensor does not work.
No 
Tap flow < 1.5 l/min.
No 
No electricity supply on flow sensor (5V DC).
No 
S3 faulty.
No 
The thermostatic shower or bath tap is faulty.
8.3.7 DHW is not reaching the correct temperature
Possible causes:
Tap flow too high.
No 
DHW temperature set too low.
CH installation becomes hot during tapping.
No 
Insufficient heat transfer due to lime scale or
contamination in the CH boiler on DHW side.
Daikin Europe NV
Replace the faulty controller. Check the wiring in accordance with the diagram.
Yes  Check the connector X4.
Replace the faulty controller.
Solution:
Clean the unit and siphon.
Yes 
Check the flue tube and the air supply system.
Solution:
Yes  Top up the installation. See par. 6.1.1.
Yes  Check the setting and adjust if required.
Increase the CH temperature See Operation CH. If there is an outdoor sensor:
Yes 
Check the outdoor sensor for short circuit: rectify this.
Check the ΔT (± 20° C) between the supply and return CH. Ensure there is good
Yes 
flow through the installation.
Yes  Adjust the boiler power. See Setting maximum CH power.
Yes  Rinse the CH boiler/installation on the side of the CH.
Solution:
Yes  Check whether the plug is in the socket.
Yes  Check the fuse, see Electrical diagram par. 10.1
Yes  Replace the flow sensor.
Yes  Increase the tap flow.
Yes  Check the wiring in accordance with the diagram.
Yes  Replace S3.
The thermostatic tap only lets through cold water. This means the tap flow through
Yes 
the boiler remains under 1.5 l/min. Check the thermostatic tap.
Solution:
Reduce the tap flow. Check the dosing disk (EKOMBG22ABV1 and
Yes 
EKOMBG28ABV1)
Yes  Increase the DHW temperature, see par. 7.1.
Unwanted circulation in the ch circuit during hot water request due to thermosiphon
Yes  effect or second pump in the CH circuit. Install a check valve in case of
thermosiphon effect or a two-way valve in case of a second pump.
Yes  Remove lime scale or rinse the CH boiler on the DHW side.
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