What happens to a compressor motor when it starts with an un-loader valve that does not function?

When a compressor motor starts with a malfunctioning un-loader valve, it may trip the overload protector. The un-loader valve is designed to relieve pressure within the compressor upon startup, allowing the motor to start under less load. If it fails to function, the compressor encounters excessive pressure, causing the motor to work harder than it should from the moment it starts.

This excess strain on the motor can lead to overheating, which activates the overload protector. The overload protector is a safety mechanism that interrupts power to the motor to prevent damage from prolonged excessive current flow. Thus, the scenario where the un-loader valve does not operate correctly leads directly to the motor's inability to start smoothly and increases the risk of overheating, resulting in the overload protection mechanism tripping to safeguard the motor.