What causes these switches to fail prematurely

While light cleaning with steel wool may temporarily restore a signal

It operates on a universal 24Vac/Vdc power supply and features a 48-inch halogen-free cable with wire leads for efficient field wiring

dry installation is typically recommended

Carrier KM680009 Sight Glass 323613-751 What causes these switches toThe Carrier KM680009 Sight Glass is a heavy duty moisture and liquid indicator engineered for commercial HVACR systems. Designed to facilitate real time monitoring of refrigerant charge and moisture levels, this 1 2 inch ODF solder fitting ensures a leak proof connection within the liquid line. The high visibility glass allows technicians to identify the presence of bubbles, indicating a low charge or a flash gas condition, while the integrated