Panasonic WH-ADC0309H3E Service Manual page 184

17.5.35 Refrigeration Cycle Abnormality (F24) (WH-UD07HE5-1 and WH-UD09HE5-1)
Malfunction Decision Conditions:
1 During compressor running (heating / cooling) for more than 10 minutes except deice, pumpdown and test
mode.
2 During heating / cooling, water outlet and water inlet difference is less than 1°C.
3 During heating / cooling, high pressure < 1MPa (143 Psi) for more than 10 minutes or < 0.2 MPa (28 Psi) for
more than 5 minutes.
4 During heating / cooling, discharge temperature - saturation temperature of high pressure ≥ 60°C.
Malfunction Caused:
1 Refrigerant shortage (refrigerant leakage).
2 Faulty indoor water inlet, indoor water outlet, compressor discharge temp sensor or high pressure sensor.
3 2/3 way valve closed.
4 Clogged expansion valve or strainer.
5 Faulty indoor or outdoor PCB (main).
Abnormality Judgment:
Continue 2 times in 30 minutes.
Check for gas leaking
Is the leaking found?
No
Check sensor characteristics
1. Water outlet sensor
2. Water inlet sensor
3. Compressor discharge sensor
Does it conform to
sensor characteristics?
Yes
Check the pressure sensor
Is the pressure sensor value
and actual mismatched?
No
Yes
Repair leak point or replace,
reclaim and recharge gas
No
Replace the sensor
Yes
Replace the pressure sensor
Check for clogged expansion
valve or strainer
Is the expansion valve or strainer
clogged (ice formed)?
No
Reclaim and recharge for a specified
amount of fresh refrigerant
Is abnormality happened again?
No
184
Yes
- Replace expansion valve and / or
strainer
- Reclaim and recharge refrigerant
Yes
- Replace the outdoor or indoor unit
PCB (main)
Procedure complete