Verify your original part number or specific furnace model compatibility with a technician before installation

Common Questions: How do I know if I need a 2-stage pump instead of single-stage

drastically reducing heat transfer efficiency and forcing the system to cycle more frequently

When a "Sensor failure" or "SNS" code is detected

Replacing the spider before total failure prevents metal-to-metal contact between the jaw hubs

Williams P043800 Pilot Generator 320734-701 Verify your original part numberThe Williams P043800 Pilot Generator is an essential OEM thermoelectric component specifically engineered for the Williams Monterey Top Vent Furnace 250 and 350 series. As a critical part of the furnace control assembly, this high grade thermocouple replacement converts thermal energy from the pilot flame into the millivoltage required to operate the gas valve without an external power source. This millivolt generator features heavy duty construction