Johnson Controls HVWHP072B32S - Abnormality of Thermistor for Water Source Unit Heat Exchanger Gas Pipe (Tg)

3-80
SM-18006
TROUBLESHOOTING
Yes
Yes
Connect it.
No
Failure of Thermistor
Failure of W.S. PCB
No
Is thermistor connected to
THM12 (Tg) on W.S. PCB?
Is resistance of thermistors
THM12 between 0.2kΩ and
840kΩ?
Refer to "Alarm Code 24"
for thermistor resistance.
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isdisplayedwhenashort(0.2kΩorless)oropensensor(840kΩormore)isdetectedforeight
minutesduringoperation.
Cause Check Item
Action
(Turn OFF Main Switch)
Event
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
Failure of Water
Source Unit
Gas Pipe
Thermistor
Tg:ThermistorforWaterSourceGasPipe
W.S.PCB:WaterSourceUnitPCB(PCB1)
Alarm
Code
AbnormalityofThermistorforWaterSourceUnitHeatExchangerGasPipe
(Tg)