Williams P271100 Flame Sensor

The Williams P271100 Flame Sensor is a critical OEM safety component engineered for precise flame rectification in Williams Forsaire counterflow furnaces. This sensor acts as the primary safeguard for the ignition sequence, utilizing a heat-resistant probe to detect the presence of a burner flame. By communicating a microamp signal back to the integrated furnace control, it ensures that the gas valve remains energized only when a steady flame is established, effectively preventing the dangerous accumulation of unburned gas within the heat exchanger. Specifically designed for high-temperature durability, the P271100 is the correct replacement flame sensor for maintaining the mechanical integrity of both top vent and direct vent furnace configurations.

For service technicians troubleshooting a furnace short cycling issue, the P271100 is a direct-fit solution to resolve "3-second shutdown" faults. This genuine Williams replacement part is built to original factory specifications, ensuring compatibility with the flame rectification circuits found in Forsaire wall furnaces. When a sensor rod becomes oxidized or contaminated, it fails to generate the necessary DC microamps, leading to immediate system lockout. Replacing a worn sensor with this OEM component restores reliable furnace flame detection and protects the heating system from inconsistent operation and safety hazards.

Key Benefits

• Optimized Safety: Ensures immediate gas shut-off if no flame is detected, preventing hazardous gas buildup.
• Direct OEM Fit: Guaranteed compatibility with Williams Forsaire 3508, 5508, 4007, and 5507 models for seamless installation.
• High-Temperature Resistance: Constructed with industrial-grade materials to withstand the intense thermal environment of the burner assembly.
• Consistent Ignition: Eliminates nuisance shutdowns and ignition failures caused by weak or failing flame signals.

Common Questions

How do I know if my Williams P271100 flame sensor is failing?
The most common symptom is the furnace igniting for a few seconds and then immediately shutting down. If the burner fires but the control board doesn't receive the proper microamp signal through the P271100 sensor, it will close the gas valve as a safety precaution.

Can I clean the flame sensor instead of replacing it?
While light oxidation can sometimes be removed with a fine abrasive like emery cloth, a sensor that is heavily pitted or has a cracked ceramic insulator must be replaced with a new Williams OEM flame sensor to ensure reliable operation.

Is this part compatible with standing pilot furnaces?
No, the P271100 is designed for modern electronic ignition systems. Older standing pilot furnaces utilize thermocouples or thermopiles, which operate on different physical principles than electronic flame rectification sensors.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.