Johnson Controls HVWHP072B32S - Page 82

3-62
SM-18006
TROUBLESHOOTING
Cause Check Item
Action
(Turn OFF Main Switch)
Event
Water
Temperature
Abnormality
Check thermistor is
correctly installed.
Faulty
Thermistor
Failure
Replace thermistor
if faulty.
Correctly install it.
Incorrect
Installation
Check connection.
T ighten, replace
connector or
repair connection
Incorrect
Connection
Check connections.
Replace W.S. PCB and
check operation.
Faulty
W.S. PCB
Failure
Replace W.S. PCB
if faulty.
Repair wiring
connection.
Disconnected
Wires for
Expansion
Valve Control
Check the Additional
Refrigerant Charge
Calculation
Charge correct amount
of refrigerant.
Insufficient Refrigerant
Check outlet temp. of
solenoid valve (SVB).
Replace solenoid valve
(SVB).
Faulty Solenoid Valve (SVB)
Check expansion valve.
Replace expansion
valve if faulty.
Faulty Expansion Valve
Check resistance
of thermistor.
Clogging of Heat
Exchanger?
Remove clogging.
Clogging of
Water Strainer?
Remove clogging.
Check Water Flow
and Water Cycle
Correctly adjust
Water Flow
Insufficient Water Flow
to Water Source Heat
Exchanger during
Heating Operation
(Refer to Section 4.2.1.7.)