Lennox Y6760, Service Manual

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Installation and Maintenance
Service Manual
9.2 Procedure of Troubleshooting
1. Malfunction of Temperature Sensor F1, F2
Main detection points:
● Is the wiring terminal between the temperature sensor and the controller loosened or poorly contacted?
● Is there short circuit due to trip-over of the parts?
● Is the temperature sensor broken?
● Is mainboard broken?
Malfunction diagnosis process:
Is the wiring terminal between the
temperature sensor and the controller
loosened or poorly contacted?
Start
Insert the temperature
sensor tightly
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
Is malfunction
eliminated
Is malfunction
eliminated
Is malfunction
eliminated
Replace it with a
temperature sensor with
the same model
Make the parts upright
Is there short circuit due to trip-
over of the parts
Is the temperature sensor normal
according to the resistance table?
Replace the mainboard with
the same model.
End