Carrier 38QUS014DS2-2 Service Manual page 88

18.3.3.9 High temperature protection of condenser (ODU P5)
When outdoor pipe temperature is more than 65° C, the unit will stop, and unit runs again when outdoor pipe
temperature less than 52° C.
High temperature protection of
High temperature protection of
condenser
condenser
Check whether the
Check whether the
condenser temperature is
condenser temperature is
Higher than 65° C
Higher than 65° C
Yes
Check whether the outdoor
Check whether the outdoor
ambient temperature is
ambient temperature is
higher than 50℃
higher than 50℃
No
Check if the outdoor unit
Check if the outdoor unit
ventilation is good
ventilation is good
Yes
Check if the outdoor fan runs
Check if the outdoor fan runs
properly
properly
Yes
Check whether the heat
Check whether the heat
exchanger is dirty
exchanger is dirty
No
Replace outdoor main
Replace outdoor main
board
board
No
Refrigerant is not enough add the
Refrigerant is not enough add the
refrigerant
refrigerant
No
Check whether the refrigerant
Check whether the refrigerant
system is ok
system is ok
No
Yes Stop the unit
Stop the unit
No
Make the outdoor unit ventilate well
Make the outdoor unit ventilate well
please refer to the solution of fan
please refer to the solution of fan
speed has been out of control
speed has been out of control
No
malfunction . Find out the cause and
malfunction . Find out the cause and
have it solved.
have it solved.
Yes
Clean the heat exchanger
Clean the heat exchanger
Check the connection
Check the connection
between temperature
between temperature
sensor and PCB.
sensor and PCB.
Yes
Check whether the
Check whether the
resistance of condenser
resistance of condenser
temp. sensor is normal
temp. sensor is normal
refer to the Appendix 1
refer to the Appendix 1
Yes
85
No Correct the connection
Correct the connection
No
Replace the temperature sensor
Replace the temperature sensor