Daikin Altherma EHYKOMB33AA - Symptom: the Pressure at the Tapping Point Is Temporarily Unusually High; Symptom: Tank Disinfection Function Is NOT Completed Correctly (AH-Error)

15 | Troubleshooting
Installer reference guide
219
EVLQ05+08CA + EHYHBH05A + EHYHBH/X08A + EHYKOMB33AA
Daikin Altherma hybrid heat pump
4P355634-1G – 2022.09
Possible causes Corrective action
The gas boiler equilibrium temperature
has not been configured correctly
Increase the "equilibrium temperature"
to activate gas boiler operation at a
higher outdoor temperature. Go to:
▪ [A.5.2.2] > Installer settings >
Heat sources > Boiler >
Equilibrium temp. OR
▪ [A.8] > Installer settings >
Overview settings [5‑01]
There is air in the system. Purge air manually or automatically. See
the air purge function in the
"Commissioning" chapter.
Too much heat pump capacity is used
for heating domestic hot water (applies
only to installations with a domestic hot
water tank)
Check and make sure that the "space
heating priority" settings have been
configured appropriately:
▪ Make sure that the "space heating
priority status" has been enabled. Go
to [A.8] > Installer settings >
Overview settings [5‑02]
▪ Increase the "space heating priority
temperature" to activate backup
heater operation at a higher outdoor
temperature. Go to [A.8] >
Installer settings > Overview
settings [5‑03]
15.3.7 Symptom: The pressure at the tapping point is temporarily unusually high
Possible causes Corrective action
Failing or blocked pressure relief valve. ▪ Flush and clean the complete tank
including the piping between pressure
relief valve and the cold water inlet.
▪ Replace the pressure relief valve.
15.3.8 Symptom: Tank disinfection function is NOT completed correctly (AH-error)
Possible causes Corrective action
The disinfection function was
interrupted by domestic hot water
tapping
Program the start-up of the disinfection
function when the coming 4hours NO
domestic hot water tapping is expected.