Johnson Controls HVWHP072B32S - Page 88

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SM-18006
TROUBLESHOOTING
Alarm
Code
Abnormality of Remote Thermistor
(for DOAS Unit)
l
 TheRUNindicator(red)ashes.
l
The indoor unit number and the alarm code are displayed on the LCD. The alarm code is displayed on
the 7-segment display of the water source unit PCB.
Thisalarmcodeisdisplayedwhenashort(0.24kΩorless)oropensensor(840kΩormore)isdetected
during a heating, cooling or fan operation.
Yes
Connect them.
No
Refer to "Alarm Code 11"
for thermistor resistance.
Failure of I.U. PCB
Is thermistor THM4
connected to THM4 of
I.U. PCB?
Remote Thermistor
Set “Thermistor for Controller” setting
at Function Setting by Controller.
Thermistor for Controller
Is I.U. air temperature detected by
Remote Thermistor (THM4) or
Thermistor for Controller?
Yes
Failure of
Thermistor
No
Is resistance of THM4
between 0.24kΩ and
840kΩ?
Cause Check Item
Action
(Turn OFF Main Switch)
Event
Failure of
Remote
Thermistor
Check resistance.
Replace remote
thermistor if faulty.
Failure
Check wiring to
I.U. PCB.
Correctly connect wires.
Incorrect Connection
Replace I.U. PCB
and check operation.
Replace I.U. PCB
if faulty.
Failure of I.U. PCB