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Napoleon · Gas fireplace troubleshooting

Main burner will not light - direct vent / vent-free

What is going on

Pilot is on but the main burner will not come on.

Likely causes

  • Thermopile leads not on valve terminals 1 & 2 (TH/TP & TP)
  • Low thermopile output
  • Blocked burner/orifice
  • No switch/remote on terminals 1 & 3
  • Faulty switch or wiring
  • Bad valve operator coil

Check in this order

  1. Confirm thermopile leads are on the 1st and 2nd valve terminals (TH/TP and TP).
  2. Test thermopile millivolts (500 mV open, min 150 mV closed).
  3. Check and clean the burner and orifice.
  4. Make sure a switch or remote is connected to terminals 1 & 3.
  5. Disconnect the switch/remote at the valve and fit a jumper across 1 & 3 - if the burner lights, the switch/remote or its wiring is the fault (see switch test).
  6. If it still will not light with the jumper, test the valve operator coil resistance and replace the valve if out of spec.

Applies to: Napoleon direct-vent and vent-free gas fireplaces (general service manual)

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Source: Napoleon (Wolf Steel) Service Manual W415-0118, Part 1-3 Troubleshooting, Main Burner Not Lighting Flowchart, p.4 / p.22. Written in our own words; check the manual for your exact model.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.