Flame Sensor - State Water Heaters SHE 50-100 NE Service Handbook

FLAME SENSOR

FLAME SENSING OPERATION
The Burner MUST BE
CONTROL SYSTEM
APPLIES AC VOLTAGE
TO FLAME SENSOR
FLAME SENSOR
CERAMIC INSULATOR
METAL CONDUCTOR
AC VOLTAGE FLOWS FROM THE FLAME
SENSOR TO THE BURNER. THE BURNER
MUST BE GROUNDED FOR CURRENT TO
FLOW. DURING THIS PROCESS THE AC
VOLTAGE IS "RECTIFIED" AND BECOMES
A DC VOLTAGE. DC MICRO AMP CURRENT
THEN FLOWS BETWEEN THE FLAME SENSOR
AND THE BURNER.
GAP BETWEEN THE FLAME SENSOR AND THE
BURNER SHOULD BE APPROXIMATELY 1/2 INCH
MINIMUM FLAME SENSING CURRENT
18
IGNITER
BURNER
FLAME
BURNER
(MUST BE GROUNDED)
Ignition Failure