Armstrong Furnace R604221-01 Switch Compatible with various Johnson Controls

Compatible with various Johnson Controls and York gas furnaces

replacing it with a manual reset version can lead to improper system cycling and safety issues

Universal Gas Compatibility: Safe for use with all gases

While designed for differential velocity pressure

and Coleman systems

Armstrong Furnace R604221-01 Switch Compatible with various Johnson ControlsThe Armstrong Furnace R604221 01 Door Switch is a critical safety interlock component designed for modern HVAC systems. This furnace door safety switch functions as a primary disconnect, ensuring the blower motor and burner assembly cannot operate when the service panel is removed. Engineered to withstand high cycle operations, this interlock switch replacement serves as a direct OEM component for Armstrong, AirEase, and Ducane units. Proper