C9" Indoor Unit: Return Water Thermistor (R4T) - Daikin ALTHERMA HT ERSQ 011 AA Service Manual

Troubleshooting by Indication on the Remote Controller
"C9 " Indoor Unit: Return Water Thermistor (R4T)
3.9
C9
Remote Control
Display
Subcode 0
Applicable Models AII indoor unit models
Method of
Malfunction detection is carried out by temperature detected by return water temperature thermistor.
Malfunction
Detection
Malfunction When the return water temperature thermistor becomes disconnected or shorted while the unit is running.
Decision Conditions
 Defect of indoor unit thermistor (R4T) for water return
Supposed Causes
 Defect of indoor unit PC board (A1P)
Troubleshooting
 Refer to thermistor resistance / temperature characteristics table on P251.
152
Be sure to turn off power switch before connecting or disconnecting connector,
Caution
otherwise parts may be damaged.
Connector is
NO
connected to X12A of
the indoor unit PC
board.
YES
Resistance
is normal when
measured after
NO
disconnecting the thermistor
(X12A) (R4T) from the
indoor unit PC board.
(7.2k ~112k )
YES
Bad wire connection
Connect the thermistor and turn
value < -43.6 C
on again.
Faulty thermistor
value > 95 C
Replace the thermistor (R4T).
Replace the indoor unit PC board (A1P).
(V2786)
Troubleshooting
ESIE09-08A