Loren Cook 778531 Belt Tensioner 320720-756 The NBR (Nitrile) seals are

The NBR (Nitrile) seals are designed for air

This Photohelic pressure switch utilizes phototransistor-actuated DPDT relays

and belt-driven compressors where reliability is critical

Common Technician Questions: What symptom indicates a failing ambient air sensor

Loren Cook 778531 Belt Tensioner 320720-756 The NBR (Nitrile) seals areThe Loren Cook 778531 Belt Tensioner is a critical OEM replacement part engineered to maintain precise drive belt tension in commercial HVACR systems. Designed for heavy duty fan and blower assemblies, this automatic tensioner utilizes a internal spring mechanism to eliminate belt slippage and reduce vibration during startup and continuous operation. As a veteran grade HVAC drive component, it facilitates optimal power transmission between the motor