Williams 7735 Limit Switch 321042-401 Heat Resistance: Constructed from high-temperature

Heat Resistance: Constructed from high-temperature alloys to resist oxidation and thermal stress

This component serves as the direct replacement for Trane RLY1003

Contractors can rely on its consistent modulating control performance to maintain system balance and optimize airflow modulation across complex ductwork networks

This is the manufacturer-recommended direct replacement

The Robertshaw 4350-127 gas thermostat is built with a mechanical snap-action mechanism that maintains calibration even under constant thermal stress

Williams 7735 Limit Switch 321042-401 Heat Resistance: Constructed from high-temperatureThe Williams 7735 Limit Switch is a critical OEM replacement part designed for high temperature safety regulation in Williams Forsaire Counterflow top vent furnaces. Engineered with a 330F fixed temperature setpoint and a 5 inch insertion depth, this high limit safety control ensures the combustion chamber does not exceed safe operating parameters. When air temperature reaches the 330F threshold, the switch opens the electrical circuit to the gas