8
Faults and malfunctions
Malfunction
Room cooler does not
Water flow too low.
cool
"Cooling" switched off (e.g. room thermostat re-
quests "Cooling", but switching time program is in
the economy phase, outside temperature too low).
Refrigerant compressor is not working.
The system is in the "Heating" operating mode.
Outside temperature < 4 °C
Cooling output for room
Water flow too low.
cooling too low
Water volume in heating system too low.
Refrigerant quantity in the heating system too low or
too high.
Installation and maintenance instructions
42
Possible cause
Possible solution
▪ Check that all stop valves of the water circuit are fully open.
▪ Check that the water filter is dirty.
▪ Check if the expansion tank is defective.
▪ Completely vent the heating system and the internal circula-
tion pump.
▪ On the controller [→ Main menu → Info → Overview
→ Psyst], check that sufficient water pressure (> 0.5 bar) is
available; if necessary, top up heating water.
▪ Check that the resistance in the water circuit is not too high
for the pump (see
Chap.
10).
▪ Check the operating mode setting.
▪ Check the request parameters.
▪ Check the date, time and switching time program settings on
the controller.
▪ With backup heater (EKBUxx) installed:
▪ Check that the backup heater heats the return flow temperat-
ure to at least 15 °C (at a low return flow temperature, the
heat pump uses the backup heater first to achieve this min-
imum return flow temperature).
▪ Check mains supply of the backup heater (EKBUxx).
▪ Thermal contactor (STB) on the backup heater (EKBUxx) has
triggered. Unlock.
▪ Switch the operating mode to "Cooling".
▪ The heat pump has automatically switched to the "Heating"
operating mode in order to guarantee frost protection if the
outside temperature continues to fall. No room cooling pos-
sible.
▪ Check that all stop valves of the water circuit are fully open.
▪ Check that the water filter is dirty.
▪ Check if the expansion tank is defective.
▪ Completely vent the heating system and the internal circula-
tion pump.
▪ On the controller [→ Main menu → Info → Overview
→ Psyst], check that sufficient water pressure (> 0.5 bar) is
available; if necessary, top up heating water.
▪ Check that the resistance in the water circuit is not too high
for the pump.
▪ Check the admission pressure in the expansion tank and wa-
ter pressure; if necessary, top up the heating water and adjust
the admission pressure.
▪ Determine causes of too low or too high refrigerant quantity in
the refrigerant circuit.
▪ If the refrigerant quantity is too low, check the refrigerant
circuit for leaks, repair and add refrigerant.
▪ If the refrigerant quantity is too high, recycle the refrigerant
and refill the system with the correct quantity.
Daikin Altherma EHS(X/H)
Daikin Altherma integrated solar unit
008.1444099_00 – 07/2018 – EN