Drop-in Replacement: Directly replaces obsolete part numbers 1171826 and 1172574 without modification

provided the linkage kit is properly aligned to avoid side-loading the actuator bearings

This sensor provides continuous feedback on the damper's exact position to the building management system

Optimized Compatibility: Suitable for natural gas

Always verify the part number against the furnace wiring diagram or cabinet labels

Johnson Controls D-251-6003 Diaphragm 30067439-890 Drop-in Replacement: Directly replaces obsoleteThe Johnson Controls D 251 6003 is a high performance replacement diaphragm specifically engineered for pneumatic actuator maintenance and repair. As a genuine Number 4 actuator part, this single piece diaphragm ensures a positive seal and consistent pressure response in critical HVAC and industrial machinery control systems. Designed for field service by veteran technicians, the D 251 6003 provides the necessary flexibility to regulate fluid or gas