Johnson Controls HVWHP072B32S - Page 102

3-82
SM-18006
TROUBLESHOOTING
Entering Water
Thermistor (THM7)
l
 TheRUNindicator(red)ashes.
l
 Theindoorunitnumber(refrigerantcyclenumber-addressnumber),thealarmcode,themodelcode
1
,
the model name
1
andthenumberofconnectedindoorunitsaredisplayedontheLCD.Thewater
sourceunitnumberandthealarmcodearedisplayedonthe7-segmentdisplayofthewatersourceunit
PCB.
Note1:Exceptforsomemodels.
Thisalarmcodeisdisplayedwhenashort(0.2kΩorless)oropensensor(840kΩormore)isdetected
duringoperation.
Yes
Yes
Connect them.
No
No
Is thermistor THM7
connected to THM7
(Ta, color: red) of
W.S. PCB?
Is resistance of THM7
between 0.2k
Ω and
840k
Ω ?
Failure of
Thermistor
Failure of W.S. PCB
Refer to "Alarm Code 24"
for thermistor resistance.
Cause Check Item
Action
(Turn OFF Main Switch)
Event
Failure of
Thermistor for
Entering Water
Temp.
Check resistance.
Replace thermistor
if faulty.
Failure
Check wiring to
W.S. PCB.
Repair wiring and
connection.
Incorrect Connection
Replace W.S. PCB
and check operation.
Replace W.S. PCB
if faulty.
Failure of W.S. PCB
W.S.PCB: WaterSourceUnitPCB(PCB1)
Alarm
Code
AbnormalityofThermistorforEnteringWaterTemperature
(WaterSourceUnitEnteringWaterThermistor)