Daikin altherma 3 M Service Manual page 78

2 | Troubleshooting
Possible failure
Air in the water circuit.
Water circuit (partially)
blocked.
Possible failure
Refrigerant shortage.
Air Purge blocked - air
trapped in water system.
Possible failure
Refrigerant pressure
sensor - higher pressure
measured than actual.
Discharge pipe thermistor
– higher temperature
measured than actual.
Expansion valve incorrect
control - superheat too
high.
Backup heater NOT
working.
Deviation of outlet water
after backup heater
thermistor will influence
the backup heater control.
Flow sensor deviation –
flow measured higher than
actual.
3‑way valve blocked.
Service manual
78
Root cause
NOT enough air purged.
Dirty water.
Root cause category: component – mechanical
Root cause
▪ Refrigerant leakage,
▪ Incorrectly charged.
Component failure.
Root cause category: component – electrical
Root cause
Deviation of refrigerant
pressure sensor (higher
value measured than
actual).
Deviation of thermistor
(higher temperature
measured than actual).
▪ Faulty suction
thermistor,
▪ Faulty expansion valve
control.
Component failure.
▪ Deviation of thermistor
(higher temperature
measured than actual),
▪ Bad contact between
sensor and pipe.
Component failure.
Component failure.
Check
▪ Check if all air purge
valves are open,
▪ Check if air purge valves
are installed on
highest points of the field
installed water circuit.
Check water circuit (unit +
field) for blockages.
Check
▪ Check refrigerant charge,
▪ Pressure test the system
to check for leakage.
Check air purge valve.
Check
Check refrigerant pressure
sensor.
Check discharge pipe
thermistor.
▪ Check suction
thermistor,
▪ Check the expansion
valve.
Check backup heater.
Check outlet water after
backup heater thermistor.
Check the flow sensor.
Check the 3‑way valve.
Repair
Purge air out of unit and
field supplied water system
and backup heater.
all
Remove possible blockages
and check the water
quality.
Repair
If required, repair the leak
and charge the correct
refrigerant amount.
Replace air purge valve.
Repair
Replace refrigerant
pressure sensor.
Replace discharge pipe
thermistor or replace PCB.
Replace suction thermistor
or replace expansion valve.
Replace backup heater.
Replace outlet water after
backup heater thermistor
or PCB A1P.
Replace the flow sensor.
Replace the 3‑way valve.
EBLA09~16DA + EDLA09~16DA
Daikin Altherma 3 M
ESIE20-06A – 2021.03