Bradford-White Corp PDV100S250, D80T725, D65T625 Service Procedure PDV24-IV, To control board

SERVICE PROCEDURE PDV24-IV

Main Burner Operation Testing

DANGER

120 volt exposure. To avoid personal injury, use caution while performing this procedure.

CAUTION

Be Careful When Making Voltage

Measurements or Jumping Terminals Not to Damage or Deform Connectors or Connector Pins.

Condition:

Main burner will not light,

Display shows “Heating” under temperature

setpoint.

Tank is cold.

		N	See “pilot will not light”
Is Pilot lit?			in “Pilot Operation
			Testing” section.
	Y
Does control board continue to spark with		Y	See “Pilot lights, no flame signal” in
pilot lit?			“Pilot Operation Testing” section.

Checking MV & MV/PV control plug pins to gas valve for 24 volts output during heating cycle (pilot must be lit with no sparking).

			N
Disconnect control wire harness from					Be sure control display is showing “Heating”,
“Control” plug of control board.				N						N
						pilot is lit and control is not sparking.
Is there 22-27 volts AC across
						Recheck voltage across control board					Replace control board.
pin terminals 5 & 8? Refer to wiring
						pin terminals 5 & 8 ((MV & MV/PV)
		diagram
								Is voltage present?
		(also see photo )
			Y
		Reconnect control plug						Y
		to control board.						Brown wire disconnected
								from “MV” terminal of gas			Ground lug of
									valve		gas valve
Disconnect brown wire lead from				Y	Check incoming gas
	“MV” terminal of gas valve.
					pressure to gas valve. if
Is there 22-27 volts AC across
							okay,
		brown wire lead & ground
					replace gas valve.
			N

Check wire harness for damage or loose connections. Repair or replace as needed.

Checking main valve (MV) voltage to gas valve.

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