Vanguard MBDV37 Owner's Operation And Installation Manual page 32

DIRECT-VENT FIREPLACE
TROUBLESHOOTING
Continued
OBSERVED PROBLEM
Pilot will not light
No gas to burner, although wall switch and
valve are set to the ON position
Frequent pilot outage
Burner goes off after a short time
Burner does not light after pilot is lit
®
POSSIBLE CAUSE
1. No gas supply, or shutoff valve is OFF
2. Air in gas line
3. Construction debris clogging pilot orifice
4. Low gas pressure
5. Control valve knob is not on the PILOT
position
6. Kinked pilot line
7. Bad valve
8. Bad thermocouple or loose connection
1. Wall switch wires defective
1. Pilot flame may be too low, causing
safety pilot to "drop out"
1. Venting recirculation problem
1. Burner orifice clogged
2. Inlet gas pressure is too low
3. Thermopile leads disconnected or im-
properly connected
4. Thermopile is defective
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32
REMEDY
1. Check to see if you have gas supply
2. Hold control valve in the PILOT position
for 2 to 3 minutes to purge air. If you smell
gas stop and wait for a few minutes before
trying to light the fireplace
3. Remove debris and dirt, inspect and
clean any other possible obstructions
4. Contact your gas supplier
5. Refer to section on pilot lighting
6. Have a qualified technician replace pi-
lot line
7. Replace control valve (see Replacement
Parts, page 35)
8. Tighten thermocouple or replace
1. Check electrical connections
1. Clean and adjust pilot flame for maximum
flame impingement on thermopile
1. Have a qualified technician check vent-
ing system for leaks or obstructions.
Have a qualified technician measure the
pilot's millivoltage
1. Clean burner (see Cleaning and
Maintenance, page 28) or replace burner
orifice
2. Contact local propane/LP or natural gas
company
3. Reconnect leads (see Wiring Diagram,
page 35)
4. Replace thermopile
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