Daikin R407C PLUS - Outdoor Unit: Malfunction of Thermistor for Outdoor Air (R1 T)

Si33-105 Troubleshooting
Troubleshooting R407C PLUS Series Heat Recovery System 175
3.19 Outdoor Unit: Malfunction of Thermistor for Outdoor Air
(R1T)
Remote
Controller
Display
H9
Supposed
Causes
!
Defect of thermistor (R1T) for outdoor air
!
Defect of outdoor unit PC board (A1P)
Troubleshooting
The alarm indicator is displayed when the fan only is being used also.
(VF045)
Resistance
is normal when
measured after
disconnecting the thermistor
(R1T) from the outdoor
unit PC board.
(3.5kΩ~
360kΩ)
Connector is
connected to X20A of outdoor
PC board (A1P).
Replace outdoor unit PC board A1P.
Connect the thermistor and turn
on again.
NO
NO
Replace the thermistor (R1T)
YES
YES
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.