Bradford-White Corp PDV80S150, D80T725, D65T625, PDV100S150, PDV100S250 Service Procedure PDV24-II

		SERVICE PROCEDURE PDV24-II
			Pressure Switch Testing
	DANGER		CAUTION
		Be Careful When Making Voltage
120 volt exposure. To avoid personal injury,		Measurements or Jumping Terminals
use caution while performing this procedure.		Not to Damage or Deform Connectors or
		Connector Pins.
	PDV(S & T) Models	Vent Safety Switch (PDV-S Models Only)

Red reset button

Check pressure switch tubing to the pressure switch. Make sure tubing does not have kinks, holes, condensate, or dirt blocking air pressure to the switch. The tubing to the blower tap attaches to the - (minus) tap on the pressure switch.

Vent safety thermal switch on PDV-S blower. Depress red reset button in center of switch. If a slight click is felt, switch opened. Check for loose or leaking burner access panel (see section on servicing burners)

Induced Draft Models (D80T725 & D65T625):

Induced Draft Models use a single tap pressure switch to measure vacuum in the flue collector. The pressure switch is located inside the control box (see photo to left). Connect a digital manometer to a tee in the pressure switch tubing and measure the vacuum with the blower operating. The vacuum should be in the range of -1.70" to -2.10" w.c. The pressure switch contacts will open at -1.25"and close by -1.40" w.c. If the vacuum is below - 1.50", check to make sure the flue damper is fully open when the blower is operating. Make sure the damper and rod are not binding. Make sure there are no restrictions in the venting system and that is at least 8" in diameter. Venting is for vertical gravity venting only. Insure that there is sufficient combustion air to the utility room.

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