Flame Rectification - State Water Heaters SandBlaster SBD71 120 Service Handbook

STEP 16
STEP 16. FLAME RECTIFICATION
Note: Flame rectification means that an alternating current (AC) signal is changed to a direct current (DC)
signal. The pilot flame is the 'switch' which connects the pilot hood to the igniter and ground. If the pilot
hood and igniter sensor had the same surface area, the flame 'switch' would conduct an AC signal.
Because the pilot surface is greater than the igniter surface, the signal becomes a DC current that the
module can interpret. The pilot hood must be properly grounded and the pilot flame must remain in contact
with both surfaces for the flame proving signal to remain constant.
If the signal is broken for just 8 tenths of a second, the heater will cycle off.
Sparking at the pilot will continue if an insufficient signal is received by the module.
Sparking at the pilot will stop almost immediately after the ignition module senses the pilot flame.
IF
Sparking continues after pilot is
established:
Sparking stops:
Technical Training Department
Ashland City, TN ©2003
SBD TANK TYPE HEATERS
SERVICE HANDBOOK

FLAME RECTIFICATION

THEN
Check wire connections
Check flame contact between hood and
lighter
Clean pilot burner surfaces
Replace pilot assembly
Go to step 17.
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