Daikin EKOMB22AAV1 Installation Instructions Manual page 51

Insufficient heat transfer due to lime scale or
contamination in the CH boiler on the tap water
side.
8.3.8 CH installation stays warm unwanted
Possible causes:
Room thermostat/weather dependent regulation
faulty or short circuited.
No
CH installation is heated due to Tap comfort.
The service display regularly shows code 7.
Daikin Europe NV
Yes Remove lime scale or rinse the CH boiler on the tap water side.
Solution/cause:
Check the wiring.
Check OpenTherm and On/off connection of the unit.
Yes
Replace the thermostat.
Replace the weather-dependent regulation.
Unwanted circulation in the CH circuit due to thermosiphon effect or second pump in
Yes the CH circuit. Install a check valve in case of thermosiphon effect or a two-way
valve in case of a second pump.
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