Carrier X-POWER Series Service Manual page 152

R410A DC Inverter Series
4.5 E7: Discharge temperature sensor error (Display on faulty unit, all the ODU in standby)
E7: Discharge temperature sensor error
The sensor port on main control
board is loosen
No
The sensor is short circuit or disabled
(Using a multi-meter to measure
resistance, if the resistance is too
small, the sensor is short circuit, if the
resistance in certain temperature is
not consistent with attached table 1,
the sensor is disabled)
No
Outdoor main control board is
damaged
4.6 E8: Outdoor unit address is wrong (Only display on faulty slave unit, all the ODU in standby)
E8: Outdoor unit address is wrong
The ODU's address is more than 3 or
be set repeatedly
No
Outdoor main control
board is damaged
170
Yes
Fasten the connecting
port
Yes
Replace the sensor
Replace the outdoor
main control board
Yes
The addresses should be set less
than 3 and differently
Replace the outdoor
main control board
Carrier service manual
Troubleshooting