Johnson Controls T-4000-2138 Plastic Cover this HVAC limit switch is

this HVAC limit switch is essential for resolving short-cycling or "blower always on" symptoms caused by a tripped or failing thermal sensor

This sequencer typically operates with an on-delay of 1 to 20 seconds and an off-delay ranging from 40 to 110 seconds

"drop-in" installation without the need for field modifications

most field technicians replace the volute gasket whenever the pump head is separated from the volute housing

including the FG6RA series

Johnson Controls T-4000-2138 Plastic Cover this HVAC limit switch isThe Johnson Controls T 4000 2138 is a professional grade beige plastic thermostat cover designed specifically for T 4000 series pneumatic room thermostats. This field standard component provides a clean, streamlined aesthetic for commercial HVAC systems where tamper resistance and a minimalist profile are required. Engineered for versatility, the T 4000 2138 supports both horizontal and vertical mounting configurations, accommodating various pneumatic