Daikin FTKS20D2VMWL, Service Manual

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SiENBE04-507A Troubleshooting
Service Diagnosis 117
4.5 Thermistor or Related Abnormality (Indoor Unit)
Remote
Controller
Display
C4, C9
Method of
Malfunction
Detection
The temperatures detected by the thermistors are used to determine thermistor errors.
Malfunction
Decision
Conditions
When the thermistor input is more than 4.96 V or less than 0.04 V during compressor
operation
∗ .
∗
(reference)
When above about 212°C (less than 120 ohms) or below about -50°C (more than 1,860 kohms).
Note:
The values vary slightly in some models.
Supposed
Causes
„ Faulty connector connection
„ Faulty thermistor
„ Faulty PCB
Troubleshooting
Check No.6
Refer to P.146
C4
: Heat exchanger thermistor
C9
: Room temperature thermistor
Check the connector connection.
Correct the connection.
Repl a ce the thermi s tor.
(Repl a ce the indoor u nit PCB.)
Repl a ce the indoor u nit PCB.
I s it norm a l?
I s it norm a l?
(R140 3 )
Check No. 6
Thermi s tor re s i s t a nce check
Be su re to t u rn off power s witch b efore connect or di s connect connector,
or p a rt s d a m a ge m a y b e occ u rred.
Caution
NO
NO
YE S
YE S