Johnson Controls T-4000-2138 Plastic Cover or an audible humming from

or an audible humming from the compressor indicating a failure to initiate the start winding

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Designed for a 1/8" compression by 1/4" MNPT connection

Can I use a 5/16" bore blade instead of the 1/4" bore 68005

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Johnson Controls T-4000-2138 Plastic Cover or an audible humming fromThe 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