Always inspect the vacuum lines for cracks before replacing the switch

accurate readings in low-light mechanical rooms

the unit is used as packaged

the terminals are clearly identified for Common

Johnson Controls A421AEC-02 Temperature Control 30067439-890 Always inspect the vacuum linesThe Johnson Controls A421AEC 02 is a heavy duty single stage electronic temperature control engineered for precision in demanding HVACR environments. This unit serves as the direct replacement for A419AEC 2 and A419AEC 2C, offering a critical upgrade for contractors maintaining refrigeration, space heating, and cooling systems. Housed in a NEMA 4X enclosure (IP66), this controller is built to withstand wash down environments and high moisture