HVAC Systems · Furnace Components
Flame Sensor
A safety device that detects the presence of flame and signals the control system to keep the gas valve open during furnace operation.
Common uses
Flame detection, safety control, gas valve operation
Common symptoms
- Ignites then shuts off
- Short heating cycles
- No flame detection
Common repairs
- Sensor cleaning
- Sensor replacement
- Wiring connections
Related terms
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