Johnson Controls HVWHP072B32S - Increase in Discharge Gas Temperature at the Top of Compressor D1-15

SM-18006
3-59
TROUBLESHOOTING
l
 TheRUNindicator(red)ashes.
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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.
If the temperature at the top of the compressor is above 270°F (132°C) for 10 minutes or above
284°F(140°C)forvesecondsduringoperation,thecompressorstopsandthentheoperationis
automatically retried. If this occurs again twice in the next 60 minutes, this alarm code is displayed.
MV1 MVB
CN10 CN12
1: Refer to "Characteristics of
Thermistor"
of "Alarm Code 23".
2: W.S. PCB Connector No. is shown
in the table.
Is thermistor on
top of compressor
reading correctly?
1
Yes
Check W.S. PCB
if compressor
discharge gas
temperature is over
270
o
F (132
o
C).
Failure of Thermistor
No
No
Is thermistor
installed correctly
on the compressor?
Yes
Install it correctly.
No
Is it at cooling or
heating mode when
alarm has occurred?
Is amount of
refrigerant correct?
Is there refrigerant leak?
Yes
Yes
Yes
Yes
Yes
Yes
Cooling
Check W.S. PCB
if compressor
discharge gas
temperature is over
270
o
F (132
o
C).
Heating Operation
Cooling Operation
Heating
No
Plug connectors
2
of W.S. PCB properly.
No
Charge correct
refrigerant volume.
No
Check
expansion valve.
No
No
Remove sudden
fluctuation of indoor
load (short path, etc.).
Repair refrigerant leaks.
Recharge refrigerant.
No
Is opening of
water source unit
expansion valve
100%?
Are connectors
2
of W.S. PCB of
water source unit
heat exchanger's
expansion valve
connected properly?
Yes
Remove sudden
fluctuation of load like
the cause of frequent
thermo-ON/OFF.
Is opening of all
operating indoor units
expansion valve 100%?
(15MBH or less is 72%)
W.S. PCB: Water Source Unit PCB (PCB1)
Model
Thermistor
Td1
(THM8)
Td2
(THM9)
(H,Y)VWH(P,R)072-120B(3,4)2S ▬
(H,Y)VWH(P,R)144-216B(3,4)2S
Alarm
Code
Increase in Discharge Gas Temperature at the Top of Compressor