If ALL safety switches are closed, the burner controller module (BCM) will start the burner fan motor (BCM terminal #8).
The BCM (burner controller module) waits
In order to prevent this air switch from being jumped out, the BCM (burner controller module) checks to insure that this circuit is open prior to
If the air flow switch closes after the burner fan is turned on, the pilot solenoid valve (BCM terminal #3) is opened for
The flame rod, which extends into the pilot flame, has 300 VAC on it from the (BCM terminal #S1). The flame lets the current flow from the flame rod to ground, which is then converted to 3 volts to 11 volts DC by the BCM (burner controller module). The “flame signal” L.E.D. (light emitting diode) on the BCM lights up.
The spark plug will turn off
The
The 3 volt DC to 11 volt DC signal from the flame rod to the BCM (burner controller module) can be measured by;
(a)Closing the manual
(b)Push the Test and Reset Button on the cover of the burner control module (BCM) in to the “test” position.
(c)Start a drying cycle... the burner controller module (BCM) will halt the ignition sequence after the pilot is ignited. The pilot flame should be about the size of a tennis ball and should make the flame sensor red hot.
(d)Insert the positive probe of a DC voltmeter in to the “flame signal” port on the cover of the burner controller module (BCM). Connect the negative probe to ground.
(e)If signal is less than 3 volts DC, then the pilot may be too small or too large, there may be a wiring connection between the flame rod and BCM (burner controller module), the flame rod may be dirty, (wash it with soap and water) or defective, or the grounding may be faulty.
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