Troubleshooting - White Mountain Hearth VSM-18-1 Owner's Manual

1. Match will not light pilot.
a. Main shut-off valve closed.
• Make sure that the shut-off valve located on the pipe
supplying gas to the fireplace is open.
b. Air in the gas line.
• Light a match, turn valve knob to "PILOT" position and
depress, keep match near pilot burner until it lights.
c. Valve knob in "OFF" position.
• Turn valve knob to "PILOT" position and depress, keep
match near pilot burner until it lights.
d. Pilot orifice plugged up, not allowing gas to flow.
• This repair requires tools and some degree of experience.
Ask serviceman for assistance.
e. No gas supply to the fireplace.
• Check plumbing to see if gas fireplace has been hooked
up to the gas supply line.
• Propane tanks is empty.
2. Pilot will not stay lit after carefully following lighting instruc-
tions for VSR—Models.
a. Defective pilot generator (thermopile), remote wall
switch.
• Check pilot flame. Must impinge on thermopile. Clean
and or adjust pilot for maximum flame impingement on
thermopile.
• Be sure wire connections from thermopile at gas valve
terminals are tight and thermopile is fully inserted into
pilot bracket.
• One of the wall switch wires may be grounded. Remove
wall switch wires from valve terminals if pilot now stays
lit, trace wall switch wiring for ground. May be grounded
to appliance or gas supply.
• Check thermopile with millivolt meter. Take reading at
thermopile terminals of gas valve. Should read 325 mil-
livolts minimum while holding valve knob depressed
in pilot position and wall switch "Off." Replace faulty
thermopile if reading is below specified minimum.
b. Defective automatic valve operator — Turn valve knob to
"On." Place wall switch to "On" millivolt meter should read
greater than 100 M.V. If the reading is okay and the burner
does not come on, replace the gas valve.
c. Defective thermopile.
• Check all connections and try.
• If still not operating, disconnect lead between thermo-
couple switch and valve operator. Then disconnect lead
to pilot magnet and connect to valve operator terminal
(TP, TH). If pilot remains lit fault lies with thermocouple.
Check that bulb is in proper location. If still not work-
ing replace thermocouple (see drawing in manual for
additional information).
Page 14

TROUBLESHOOTING

SYMPTOMS-POSSIBLE CAUSES AND CORRECTIONS
3. Pilot burning, no gas to burner, valve knob "On," wall
switch "On."
a. Wall switch or wires defective.
• Check wall switch and wires for proper connections.
Jumper wire cross terminals at wall switch, if burner
comes on, replace defective wall switch. If okay, jumper
wires cross wall switch wires at valve, if burner comes
on, wires are faulty or connections are bad.
b. Thermopile may not be generating sufficient millivoltage.
• Replace.
c. Plugged burner orifice.
• Check burner orifice for debris and remove.
4. Pilot will not stay lit after carefully following lighting in-
structions for VSM—Models.
a. Defective thermocouple.
• Check that pilot flame impinges on thermocouple. Clean
and/or adjust pilot for maximum flame impingement.
• Ensure that the thermocouple connection at the gas valve
is fully inserted and tight (hand tight plus 1/4 turn) faulty
thermopile if reading is below specified minimum.
• 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 15 mv, replace the
thermocouple.
b. Defective valve.
• If thermocouple is producing more than 15 millivolts,
replace faulty valve.
5. Frequent pilot outage problem.
a. Pilot flame may be too low or blowing (high) causing the
pilot to drop out.
• Clean and/or adjust flame for maximum flame impinge-
ment on thermopile or thermocouple.
6. Main burner flame is too low or too high.
a. Check inlet supply pressure for "M" and "R" models.
b. Check manifold pressure on gas valve for "R" models and
inlet regulator on "M" models.
14015-6-0907