Carrier 38QUS012D8S Service Manual page 114

2.4.1.3. Indoor EEPROM Malfunction
Malfunction conditions
Possible causes
EEPROM: An electrically erasable programmable read-only memory whose contents can be erased and
reprogrammed using a pulsed voltage.
2.4.1.4. Water-Level Alarm Malfunction
Malfunction conditions
Possible causes
Power off, then restart the unit 2 minutes
Power off, then restart the unit 2 minutes
later. Is it still displaying the error code?
later. Is it still displaying the error code?
Yes
Is the water-level
Is the water-level
switch inserted
switch inserted
properly?
properly?
Yes
Is the water-level
Is the water-level
switch broken?
switch broken?
No
Replace the water pump. Is
Replace the water pump. Is
the malfunction still not
the malfunction still not
resolved?
resolved?
Yes
Replace the indoor main PCB
Replace the indoor main PCB
Electrical Control System
Main PCB chip does not receive feedback from EEPROM chip
● Installation mistakes
● Faulty PCB
If the sampling voltage is not 5V, the LED will display the failure
code.
Wiring mistakes
●
Faulty water-level switch
●
Faulty water pump
●
Faulty indoor PCB
●
Insert the water-level switch
Insert the water-level switch
No
Yes Replace the water-level switch
Replace the water-level switch
properly
properly
Troubleshooting
112