Hearth and Home Technologies SL-750TV-D Troubleshooting, Standing Pilot Ignition System

14 Troubleshooting

With proper installation, operation, and maintenance your gas appliance will provide years of trouble-free service. If you do experience a problem, this troubleshooting guide will assist a qualified service person in the diagnosis of a problem and the corrective action to be taken. This troubleshooting guide can only be used by a qualified service technician.

A. Standing Pilot Ignition System

Symptom	Possible Causes	Corrective Actions
1. After repeated	a. Defective ignitor.	Check the spark at the electrode and pilot. If no spark and electrode wire
triggering of the		is properly connected, replace the ignitor.
red or black piezo
ignitor button, the
	b. Defective pilot	Using match, light the pilot. If the pilot lights, turn off the pilot and trigger
spark ignitor will not
	or misaligned	the red piezo ignitor button again. If the pilot lights, an improper gas/air
light the pilot.
	electrode (spark at	mixture caused the bad lighting and a longer purge period is recom-
	electrode).	mended. If the pilot will not light, ensure the gap at the electrode and pilot
		is one-eighth (1/8) inch to have a strong spark. If the gap is OK, replace
		the pilot.
	c. No gas or low	Check the remote shut-off valves from the fireplace. Usually, there is a
	gas pressure.	valve near the gas main. There can be more than one (1) valve between
		the fireplace and the main.
	d. No LP in tank.	Check the LP (propane) tank. You may be out of fuel.
2. The pilot will not	a. Defective ther-	Check that the pilot flame impinges on the thermocouple. Clean and/or
stay lit after care-	mocouple.	adjust the pilot for maximum flame impingement.
fully following the
lighting instructions.		Ensure that the thermocouple connection at the gas valve is fully inserted
		and tight (hand tighten plus 1/4 turn).
		Disconnect the thermocouple from the valve, place one millivolt meter
		lead wire on the tip of the thermocouple and the other meter lead wire on
		the thermocouple copper lead. Start the pilot and hold the valve knob in. If
		the millivolt reading is less than 15mV, replace the thermocouple.
	b. Defective valve.	If the thermocouple is producing more than 15 millivolts, replace faulty
		valve.
3. The pilot is	a. ON/OFF switch	Check the ON/OFF switch and wires for proper connections. Place the
burning, there is	or wires defective.	jumper wires across the terminals at the switch. If the burner comes on,
no burner flame,		replace the defective switch. If the switch is OK, place the jumper wires
the valve knob is		across the switch wires at the gas valve. If the burner comes on, the wires
in the ON position,		are faulty or connections are bad.
and the ON/OFF
	b. Thermopile may	If the pilot flame is not close enough physically to the thermopile, adjust
switch is in the ON
	not be generating	the pilot flame.
position.
	sufficient millivolt-
	age.	Be sure the wire connections from the thermopile at the gas valve termi-
		nals are tight and that the thermopile is fully inserted into the pilot bracket.
		Check the thermopile with a millivolt meter. Take the reading at TH-
		TP&TP terminals of the gas valve. The meter should read 325 millivolts
		minimum, while holding the valve knob depressed in the pilot position,
		with the pilot lit, and the ON/OFF switch in the OFF position. Replace the
		faulty thermopile if the reading is below the specified minimum.
		With the pilot in the ON position, disconnect the thermopile leads from
		the valve. Take a reading at the thermopile leads. The reading should be
		325 millivolts minimum. Replace the thermopile if the reading is below the
		minimum.

Heat & Glo • SL-550 / 750 / 950TV-D • 2053-985 Rev. H • 9/06 35