Thermocouples & Thermopiles

Resideo thermocouples and thermopiles for standing pilot gas appliances. The collection includes Q340 thermocouples in 18", 36" and 48" lengths, Q390 30 mV thermocouples, Q313 750 mV thermopiles with push-in clips, PG9 adapters or split nuts, and the Q313U multi-system thermopile generator.

A thermocouple produces a small voltage that holds a gas valve open, while a thermopile generates enough millivolts to power a millivolt gas valve and control circuit. Match the type to the gas valve, choose a length that reaches without sharp bends, and confirm the connection end and pilot bracket fitting.

See also: Controls, Switches & Sensors, Gas Ignition Components, Pilot, Burner & Ignition Parts.

Popular part numbers: Resideo Q340A1066, Resideo Q390A1061, Resideo Q313A1170.

Frequently asked questions

What is the difference between a thermocouple and a thermopile?

A thermocouple makes a small voltage that holds the pilot valve open. A thermopile makes enough millivolts to run a millivolt gas valve and its control circuit, so the two are not interchangeable.

What length do I need?

Choose a lead long enough to reach the gas valve without sharp bends. Measure the old one or check its part number.

Do these fit Honeywell gas valves?

Yes. Resideo now makes the Honeywell Home line, so Q340, Q390 and Q313 numbers carry over. Browse all Resideo parts.