Gas Fireplace: SIT 820 Nova millivolt valve: pilot will not stay lit
SIT 820 Nova millivolt valve: pilot will not stay lit on a gas fireplace: The pilot lights while the knob is held but goes out when released, or drops out later.
Applies to: Fireplaces and gas logs with SIT 820 Nova MV / Millivolt Plus valves
Common causes of sit 820 nova millivolt valve: pilot will not stay lit
- Wrong inlet pressure
- Pilot flame too small or not on the thermocouple/thermopile
- Thermocouple or thermopile not fully seated, dirty or failed
- Failed safety magnet in the valve
- Wrong or blocked pilot orifice
How to fix sit 820 nova millivolt valve: pilot will not stay lit: step by step
- Relight and hold the knob in for 30 seconds before releasing.
- Check the thermocouple and thermo-generator are fully inserted in the pilot; thermocouple tight in the valve = hand tight plus 1/4 turn with a wrench. Clean the tips (upper 3/8 in.) with very fine emery cloth.
- Millivolt Plus: open-circuit thermocouple voltage should be 18-28 mV; under 14 mV = replace the thermocouple.
- Safety magnet (mV Plus): hold the pilot button, reconnect the thermocouple, measure between the solder button on the magnet and the valve body. Above 6 mV (vented) or 8.5 mV (unvented) and the magnet will not hold = replace the valve. Closed-circuit reading equal to open-circuit = open coil, replace the valve.
- Millivolt system: remove the operator wires and measure TPTH to TP; above 110 mV and the magnet will not hold = replace the valve.
- Replace a blocked or wrong pilot orifice with the exact one for the appliance and gas type.
If the unit shows an error code, look it up: Heat & Glo Gas Fireplace codes Napoleon Gas Fireplace codes Skytech Gas Fireplace codes
Source: SIT 820 Nova MV Troubleshooting Guide; SIT Gas Control Valve troubleshooting flow chart (Fireparts). 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.