Gas Fireplace: Flameworks millivolt valve: pilot outage or burner will not come on
Flameworks millivolt valve: pilot outage or burner will not come on on a gas fireplace: Fireplace or heater with a Flameworks millivolt or 3 V gas valve: pilot will not stay lit, or the main burner will not come on.
Applies to: Appliances with Flameworks millivolt or 3 V gas valves
Common causes of flameworks millivolt valve: pilot outage or burner will not come on
- Pilot flame not covering the thermocouple/thermopile tip
- Low thermocouple or thermopile output
- Weak automatic pilot magnet
- Failed valve operator
- Too much resistance in thermostat leads
How to fix flameworks millivolt valve: pilot outage or burner will not come on: step by step
- Lighting: knob to PILOT, push and light, hold 2 minutes before releasing. If the pilot lights without pushing the knob, replace the valve.
- Pilot flame should cover the upper 3/8 in. of the thermocouple/thermopile tip; adjust with the pilot screw, never with the knob.
- Thermocouple (non-millivolt): closed-circuit output under 8 mV = replace the thermocouple. Magnet check: a good magnet stays latched for a drop of at least 5 mV from the stabilized reading, otherwise replace the valve.
- Millivolt: thermopile output should be 250-750 mV. Test A (terminals 2 & 3, thermostat closed) above 100 mV but valve not opening = replace the valve operator. Test B (1 & 3, thermostat closed) below 325 mV = clean/tighten connections, adjust pilot, else replace the thermopile. Magnet is good if it stays latched down to 120 mV or less.
- Test C (thermostat circuit) too high = clean/tighten thermostat leads, shorten them or use heavier wire, or replace the thermostat. Max wire: 14 ga 100 ft, 16 ga 64 ft, 18 ga 40 ft, 20 ga 25 ft, 22 ga 16 ft.
- Do not exceed 1/2 psi (14 in. w.c.) inlet. Replace any valve that has been under water or will not shut off.
If the unit shows an error code, look it up: Heat & Glo Gas Fireplace codes Napoleon Gas Fireplace codes Skytech Gas Fireplace codes
Source: Flameworks Gas Valves Installation Manual (millivolt / 3 V), p.2-4. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.