Johnson Controls T-4000-2139 Cover Safety Compliance: Engineered to meet

Safety Compliance: Engineered to meet strict manufacturer safety standards for HVAC temperature regulation and fire prevention

Rugged Construction: Built with a heavy-duty steel frame and a ladder hook for convenient storage while working at heights

the HH18HA490 is the official updated replacement part designed to meet or exceed the specifications of the HH18HA292

This heavy-duty 120V to 24V step-down transformer is engineered for continuous-duty applications where stable secondary voltage is critical for powering sensors

Johnson Controls T-4000-2139 Cover Safety Compliance: Engineered to meetThe Johnson Controls T 4000 2139 is a professional grade horizontal thermostat cover designed specifically for the T 4000 Series pneumatic room thermostats. Engineered for sleek, unobtrusive installation, this beige plastic cover features a clean aluminum faceplate without a thermometer window or setpoint adjustment openings. This configuration is ideal for facilities where unauthorized tampering must be minimized while maintaining a uniform aesthetic