Check Points, Maintenance and Troubleshooting
80
Air-to-Water Heat Pump
Troubleshooting for Error Code
Code
No.
Description
Cause
Normal Condition
1
Problem in remote room air sensor
• Incorrect connection between
sensor and PCB.
• PCB fault
• Sensor fault
• Resistance: 10 k
Ω
at 25
centigrade (unplugged)
→
for
Remote room air sensor
• Resistance: 5 k
Ω
at 25 centigrade
(unplugged)
→
for all sensors
EXCEPT remote room air sensor
• Voltage: 2.5 V DC at 25 centigrade
(plugged) (for all sensors)
• Refer resistance-temperature table
to check in different temperature
2
Problem in refrigerant (inlet side) sensor
6
Problem in refrigerant (outlet side) sensor
8
Problem in water tank sensor
16
Problems in sensors
17
Problem in water-inlet sensor
18
Problem in water-outlet sensor
19
Problem in water-interim sensor
3
Bad communication between remote
controller and unit.
• Incorrect connection between
sensor and PCB
• PCB fault
• Sensor fault
• Wire connection between remote
controller and Main PCB Assembly
1 should be tight
• Output voltage of PCB should be
12 V DC
5
Bad communication between Main PCB
Assembly 2 and Main PCB Assembly 1 of
the unit.
• The connector for transmission is
disconnected
• The connecting wires are
misconnected
• The communication line is broken
• Main PCB Assembly 2 is abnormal
• Main PCB Assembly 1 is abnormal
• Wire connection between remote
controller and Main PCB Assembly
1 should be tight
53
9
PCB program (EEPROM) fault
• Electrical or mechanical damage a
the EEPROM
• This error can not be permitted
14
Problem in flow switch
• Flow switch is open while internal
water pump is working
• Flow switch is closed while internal
water pump is not working
• Flow switch is open while DIP
switch No. 5 of Main PCB
Assembly 1 is set as on
• Flow switch should be closed while
internal water pump is working or
DIP switch No. 5 of Main PCB
Assembly 1 is set as on
• Flow switch should be open while
internal water pump is not working
15
Water pipe overheated
• Abnormal operation of electric
heater
• Leaving water temperature is
above 75 ℃
• If there is no problem in electric
heater control, possible maximum
leaving water temperature is 75 ℃
20
Thermal fuse is damaged
• Thermal fuse is cut off by abnormal
overheating of internal electric
heater
• Mechanical fault at thermal fuse
• Wire is damaged
• This error will not be happened if
temperature of electric heater tank
is below 90 ℃
