Daikin FTKS20CVMB(9), Service Manual

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Troubleshooting SiENBE04-512A
106 Service Diagnosis
4.5 Thermistor or Related Abnormality (Indoor Unit)
Remote Control
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.132
C4
: Heat exchanger thermistor
C9
: Room temperature thermistor
Check the connector connection.
YE S
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 )
NO
Check No. 6
Thermi
s tor re s i s t a nce check
YE S
NO
Caution
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.
SiENBE04-512A.book Page 106 Friday, October 5, 2007 1:49 PM