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Low-Pressure Controls Explained | Commercial Refrigeration

By Jeff Crable Sam Behncke

April 22, 2026

In this video, we break down how low-pressure controls work in commercial refrigeration systems — what they do, how to test them, and why they matter for protecting your compressor.

We cover common failures, including stuck relays and cracked capillary tubes, and walk through how to properly set cut-in and cut-out ranges for different refrigerants. We also explain the pump-down cycle, why it’s critical to test on every PM and service call, and what symptoms to look for when a pressure control isn’t functioning correctly.

Whether you’re new to the trade or brushing up your skills, understanding how these controls are explained here can save your customer from a costly compressor replacement.

#commercial refrigeration #controls #hvac #low-pressure controls #pump down #refrigeration

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