Carrier HH12ZB330 Limit Switch 322055-301 Engineers often specify the MP-424

Engineers often specify the MP-424 as a direct replacement for Barber Colman EA-51

Rugged Hardware: Cast bronze construction and brass seats are engineered to withstand the thermal stresses of steam and hydronic HVAC cooling and heating

The switch utilizes a snap-disc mechanism that is factory-calibrated to cut power to the gas valve or heating elements when the internal plenum temperature reaches a 150

Key Benefits: Engineered Protection: Prevents tool drops and large foreign objects from compromising expensive fan blades and condenser motors

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Carrier HH12ZB330 Limit Switch 322055-301 Engineers often specify the MP-424The Carrier HH12ZB330 is a critical safety component designed for high temperature furnace and HVAC applications. This 300 330F auto limit switch functions as a primary thermal protection device, monitoring internal heat levels to prevent heat exchanger damage or unsafe operating conditions. As an OEM Carrier replacement part, it ensures factory spec calibration and reliability, which is essential when troubleshooting rollout issues or overheating