Troubleshooting for SkyAir Indoor Unit
Si18-525B
350
Troubleshooting
5.8
Malfunction of Heat Exchanger Thermistor (R2T)
Remote
Controller
Display
C4
Applicable
Models
FFQ, FCQ, FBQ, FHQ
Method of
Malfunction
Detection
Malfunction detection is carried out by temperature detected by heat exchanger sensor.
Malfunction
Decision
Conditions
When the heat exchanger thermistor becomes disconnected or shorted while the unit is running.
Supposed
Causes
Failure of the sensor itself
Broken or disconnected wire
Failure of electronic circuitry (indoor unit PCB)
Failure of connector contact
Troubleshooting
Check No.02
Refer to P.358
Disconnect the heat exchanger
sensor (R2T) from X18A on
the indoor unit PCB and
measure the resistance.
Connect correctly.
Heat exchanger
sensor replacement.
If contact is OK,
replace indoor unit
PCB.
Is the
thermistor normal?
(See note)
NO
NO
YES
YES
(Q0416)
Check contact of connector
Is it normal?
+
See
Check No. 02
for “Thermistor temperature and resistance characteristics”.
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Summary of Contents for D-Series
Page 1: ...Si18 525B Applied Models Super Multi Plus Cooling only Super Multi Plus Heat Pump D Series ...
Page 33: ...List of Functions Si18 525B 20 List of Functions ...
Page 71: ...Specifications Si18 525B 58 Specifications ...
Page 117: ...Refrigerant Flow for Each Operation Mode Si18 525B 104 Refrigerant Circuit ...
Page 171: ...Indoor Unit SkyAir Models Si18 525B 158 Function ...
Page 207: ...Test Operation and Field Setting for RA Indoor Unit Si18 525B 194 Test Operation ...
Page 336: ...Si18 525B Service Check Function Troubleshooting 323 ...
Page 469: ...Wiring Diagrams Si18 525B 456 Appendix ...
Page 475: ...Si18 525B vi Index ...