Bradford-White Corp EF100T399(E)*(N From previous, Replace blower, Section Combustion System

System Observation

For models with Direct Spark Ignition

From previous page

WARNING

120 volt potential exposure. Use caution

making voltage checks to avoid personal injury.

Does combustion blower operate?

Y

CAUTION

Use caution not to damage connectors when

making voltage measurements or jumping terminals

			Replace control board if display
	Error code #29 on display. Refer to Control Board	N	shows “heating” and no voltage is
N	illustration. Measure voltage between terminals P7(3) &		present to the blower harness.
	P7(5) on the “inducer” output (make sure the control display		Make sure there are no error
	shows “heating” in the status mode, if not increase the		codes for the temperature
	setpoint). Is there 110-120 VAC?		sensors (following sections)
			before replacing control board.

Y

Replace blower.	Y Check the voltage at the connection to the		N	Replace wire harness.
		blower. Is 110-120 VAC present?

Can sparking be seen/heard at the

spark rod to the burner?

Y

Does Main Burner Light?

Y

Does burner continue until

thermostat set point is reached?

See setting display in Service Mode

and displaying temperature

sensors.

Y

Does blower post-purge for 30

seconds?

Y

System okay

		Remove high voltage wire connected at the spark rod and							Check resistance of high voltage
N								N	cable. Resistance should be 0-1
		hold approximately ¼" from metal ground with insulated							ohms. If resistance is high, replace
	pliers during the ignition cycle (3 second spark trial period).								spark cable. If spark cable is good,
				Is there spark to ground?					replace Control Board.
						Y
					Check continuity of spark rod and spark rod
		Error code #62 on display. See					gap to burner.
N					(see section “Spark Rod Gap Adjustment”)
		main burner lights, no flame signal
		in section “Combustion System
			Testing and Replacement”
					Check to see if control display shows any other error
		Error code #63 on display. (see			codes (29, pressure switch, 26, vent safety switch, or 65,
N		“Combustion System Testing and			high limit). If so, refer to the appropriate section for
				Replacement”)				testing and replacement.

CONTROL BOARD

3		1	2
2
1	6	3			1	1	3
8	5
		1	2	3			5
					3		1
	4	1
						4
J1	P5	P4	P9	P10	P2	P3	P7	19

19