Johnson Controls HMH72B36 User Manual

Table 10: Outdoor unit fault codes
Fault code Fault description Possible reasons for fault Resolution Comments
13
Compressor overheat
protector device
1. The wiring of
the overload
protector has a poor
connection.
2. Overload protector
failure.
3. Low refrigerant
charge.
4. Long lineset length
applied without
additional charge.
5. TXV/EEV valve failure.
6. Outdoor control board
failure.
1. Reconnect the wiring
of the overload
protector.
2. Replace the overload
protector.
3. Check the braze
joints for leaks
and recharge the
refrigerant.
4. Add refrigerant.
5. Replace the
expansion valve.
6. Replace the outdoor
control board.
14
The high-pressure
switch operation or
unit is turned off
for high-pressure
protection
1. The wiring of the high-
pressure switch has a
poor connection.
2. The high-pressure
switch has failed.
3. The outdoor control
board is abnormal.
4. Overload in cooling.
5. Overload in heating.
1. Reconnect the wiring
of the high-pressure
switch.
2. Replace the high-
pressure switch.
3. Replace the outdoor
control board.
4. See Table 11.
5. See Table 12.
Applies to models
with high-
pressure switch
or pressure
sensor.
15
The low-pressure
switch protection
or unit is turned off
for low-pressure
protection
1. The wiring of the low-
pressure switch has a
poor connection.
2. The low-pressure
switch has failed.
3. The refrigerant charge
is low.
4. The expansion valve
fails in heating mode.
5. The outdoor control
board is abnormal.
1. Reconnect the wiring
of the low-pressure
switch.
2. Replace the low-
pressure switch.
3. Check for a
refrigerant leak and
adjust the refrigerant
charge.
4. Replace the
expansion valve.
5. Replace the outdoor
control board.
Applies to
models with low-
pressure switch
or pressure
sensor.
16
Overload protection
in cooling mode
System overload See Table 11.
17
Discharge
temperature sensor
fault
1. The wiring of
the discharge
temperature
sensor has a poor
connection.
2. The discharge
temperature sensor
has failed.
3. The sampling circuit is
abnormal.
1. Reconnect the wiring
of the discharge
temperature sensor.
2. Replace the
discharge
temperature sensor.
3. Replace the outdoor
control board.
Installation Manual: HMH7 Series - 17 SEER Horizontal Discharge Modulating Heat Pump 37
Johnson Controls Ducted Systems

Johnson Controls HMH72B36 Specifications

General

Brand	Johnson Controls
Model	HMH72B36
Category	Heat Pump
Language	English