HVACopedia

Majestic · Gas fireplace troubleshooting

Millivolt: pilot on, knob ON, but burner will not light

DVBL7 Millivolt

What is going on

Pilot is burning and the control knob and switch are on but the main burner stays off.

Likely causes

  • Wall switch, remote or wiring faulty
  • Pilot flame too far from the thermopile
  • Thermopile weak
  • Bad gas valve

Check in this order

  1. Jumper across the wall switch terminals burner comes on means replace the switch; test the remote the same way
  2. Jumper across TH and TP/TH at the valve burner comes on means bad wire or connection
  3. Adjust the pilot so the flame reaches the thermopile
  4. Meter thermopile at TP and TP/TH below 325 mV replace the pilot assembly
  5. With knob ON and switch ON, above 175 mV and no burner: replace the valve

Applies to: 400DVBLN/PV7, 500DVBLN/PV7 (millivolt)

More gas fireplace guides

Related

Majestic error codes · Majestic parts · Majestic tips · Calculators and reference tables

Take it to the job

All guides, error codes and tips work offline in the HVACopedia app.

Open the app

Source: Majestic DVBL7 Series Installation and Operating Instructions, p. 46. 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.