White-rodgers 3l01-300 Snap Disc Fan Control Spst

Product Description

The WHITE-RODGERS 3l01-300 is a snap disc fan control designed for airstream temperature sensing in forced-air heating systems. It uses a single-pole, single-throw (SPST) switching configuration and features a flanged mount for secure installation directly in the airstream. When the sensed air temperature reaches the disc's calibrated setpoint, the bimetal disc snaps open or closed to switch the fan circuit. Licensed HVAC technicians install this control as part of furnace fan circuit management, ensuring the blower starts and stops at the correct duct-air temperatures.

This snap disc fan control is suited for residential and light-commercial gas furnace applications where a reliable, self-contained temperature-actuated switch is required in the supply-air duct or heat exchanger plenum. The flanged airstream mount allows direct insertion into the duct wall, positioning the sensing disc in the moving airstream for accurate temperature response. It is a common replacement control on older and current forced-air furnace installations requiring SPST snap-action switching.

Key Features

• SPST snap-disc switching provides clean, positive open and close action
• Flanged airstream mount design allows direct duct-wall installation
• 3/4 inch flange mount fits standard furnace and air-handler duct knock-outs
• Bimetal disc construction requires no external power to actuate
• Self-contained design simplifies replacement on existing furnace fan circuits

Compatibility

Designed as an OEM-style replacement snap disc fan control for residential and light-commercial forced-air furnace systems requiring a flanged airstream-mount SPST switching control.

Installation Notes

A licensed HVAC technician should perform this installation. Disconnect all power to the furnace at the disconnect switch and confirm the system is de-energized before removing the existing control or handling wiring. Insert the flanged disc into the duct or plenum opening and secure the flange hardware before reconnecting wiring. Follow applicable local mechanical and electrical codes, and verify correct fan-on and fan-off operation through a complete heating cycle before returning the system to service.

Technical Specifications

• Switch Type: SPST (Single-Pole, Single-Throw)
• Mount Type: Flanged Airstream Mount
• Flange Size: 3/4 inches
• Control Type: Snap Disc Fan Control
• UPC: 786710001963

Standard Information

• Brand: WHITE-RODGERS
• Manufacturer Part Number: 3l01-300