Panasonic WH-ADC0916G9E8, Service Manual, Page: 107 / 205

107
17.4 Error Codes Table
Diagnosis display Abnormality/Protection control Abnormality judgement Primary location to verify
H00 No abnormality detected — —
H12 Indoor/Outdoor capacity unmatched 90s after power supply

Indoor/outdoor connection wire

Indoor/outdoor PCB

Specification and combination table in
catalogue
H15
Outdoor compressor temperature sensor
abnormality
Continue for 5 sec.

Compressor temperature sensor
(defective or disconnected)
H20 Water pump abnormality Continue for 10 sec.

Indoor PCB

Water pump (malfunction)
H23
Indoor refrigerant liquid temperature
sensor abnormality
Continue for 5 sec.

Refrigerant liquid temperature sensor
(defective or disconnected)
H27 Service valve error Continue for 5 minutes

High pressure sensor (defective or
disconnected)
H42 Compressor low pressure abnormality —

Outdoor pipe temperature sensor

Clogged expansion valve or strainer

Insufficient refrigerant

Outdoor PCB

Compressor
H62 Water flow switch abnormality Continue for 1 min. 
Water flow switch
*H63 Refrigerant low pressure abnormality Continue for 5 sec.

Outdoor low pressure sensor
(defective or disconnected)
H64 Refrigerant high pressure abnormality Continue for 5 sec.

Outdoor high pressure sensor
(defective or disconnected)
*H65 Deice circulation error Continue for 10 sec.

Water flow switch sensor (defective or
disconnected)

Water pump malfunction

Buffer tank (is used)
H70 Back-up heater OLP abnormality Continue for 60 sec.

Back-up heater OLP
(Disconnection or activated)
H72 Tank sensor abnormal Continue for 5 sec.

Tank sensor
H76
Indoor - control panel communication
abnormality
—

Indoor - control panel
(defective or disconnected)
H90 Indoor/outdoor abnormal communication > 1 min after starting operation

Internal/external cable connections

Indoor/Outdoor PCB
H91 Tank heater OLP abnormality Continue for 60 sec.

Tank heater OLP
(Disconnection or activated)
H95 Indoor/Outdoor wrong connection — 
Indoor/Outdoor supply voltage
H98
Outdoor high pressure overload
protection
—

Outdoor high pressure sensor

Water pump or water leakage

Clogged expansion valve or strainer

Excess refrigerant

Outdoor PCB
H99 Indoor heat exchanger freeze prevention —

Indoor heat exchanger

Refrigerant shortage
F12 Pressure switch activate
4 times occurrence within
20 minutes

Pressure switch
F14 Outdoor compressor abnormal revolution
4 times occurrence within
20 minutes

Outdoor compressor
F15 Outdoor fan motor lock abnormality
2 times occurrence within
30 minutes

Outdoor PCB

Outdoor fan motor
F16 Total running current protection
3 times occurrence within
20 minutes

Excess refrigerant

Outdoor PCB
F20
Outdoor compressor overheating
protection 4 times occurrence within
30 minutes

Compressor tank temperature sensor

Clogged expansion valve or strainer

Insufficient refrigerant

Outdoor PCB

Compressor
F22
IPM (power transistor) overheating
protection 3 times occurrence within
30 minutes

Improper heat exchange

IPM (Power transistor)
F23
Outdoor Direct Current (DC) peak
detection 7 times occurrence
continuously

Outdoor PCB

Compressor
F24 Refrigeration cycle abnormality
2 times occurrence within
20 minutes

Insufficient refrigerant

Outdoor PCB

Compressor low compression
F25
Cooling/Heating cycle changeover
abnormality 4 times occurrence within
30 minutes

4-way valve

V-coil
F27 Pressure switch abnormality Continue for 1 min.

Pressure switch