Vermont Casting NVC39 Vent Safety Switch, Electrical Connection, NVC Series B-Vent, 20000194

NVC Series B-Vent

Vent Safety Switch

This fireplace incorporates the use of a Vent Safety Shut-off Switch. The sensor and wiring are factory installed and should not be removed or altered during installation.

In the event of total flue blockage the system will detect the increased heat buildup and will automatically shut down the main burner assembly.

The sensor is located above the firebox behind the top louvre assembly. It is accessible by removing the top louvre assembly.

CAUTION: The firebox, Vent Safety Switch sensor and surrounding panels become very hot during normal operation. Allow time for the components to cool before carrying out any service or inspection.

If the sensor is activated and shuts off the burner as- sembly, the following procedure should be followed:

•Observe that the pilot flame is still ON. If the pilot flame has gone out the reason for the fireplace shut down is not the vent safety switch.

•Turn the pilot flame OFF and close all controls. Allow the fireplace to cool.

•Check the flue and venting components for blockage or restrictions.

•Remove the front louvre assembly.

•Locate the sensor.

•Reset the sensor by pressing the reset pin between the two wire terminals. (Fig. 18)

CAUTION: The components may still be hot.

•Light the fireplace and check for downdrafts.

•Operate the fireplace in the normal manner. If the burner assembly shuts down again after a period of operation, DO NOT ATTEMPT TO RESET THE SENSOR AGAIN. Turn off the fireplace and contact your service technician.

Sensor

Wire Ter-
minal	Wire Terminal
	Reset Pin
	FP1160

Fig. 18 Vent Safety Switch.

14

Electrical Connection

The sensor is wired in series between the wall mounted ON/OFF switch and the Electronic Ignition Module (Fig. 19) or the thermopile and the gas valve (Fig. 20)

WHITE

PILOT

HONEYWELL S8600 B IGNITION MODULE								BLACK
MV MVPV PV	GND		24V	24V		SENSE	SPARK
	(BURNER)		GND
	WHITE
						WHITE
		BLACK
BLACK	WHITE
							BLACK
WHITE
						A	E
				L	O
			O			H
			L
						I
				IH
		T	P
		OLI
	NOVA SIT 822 VALVE
							BLACK
120 VAC RTN			24 VAC HOT					BLACK
WHITE	1	5	BLACK			WHITE
BLACK	3	4	WHITE
								ON-OFF
120 VAC HOT			24 VAC RTN
								SWITCH

GREEN40VA

TRANSFORMER

FP670

Fig. 19 Vent Safety Switch wiring, EN/EP units.

	Thermopile
OnN/OFF
Switch
Vent
Safety	TH
Switch		Gas
	TP
		Valve
	TH
	TP
		FP1161
Fig. 20	RN/RP units using a remote ON/OFF switch.
		20000194