The function of the safety head on a compressor is to prevent what issue?

• A. Valve plate damage due to liquid slugging
• B. Overheating
• C. Electrical fault
• D. Loss of lubrication

Answer: (A)

The safety head is there to protect the compressor from damage when liquid returns to the cylinder. If liquid refrigerant slugs back into the compressor, liquids are incompressible and can slam into the valve plates, causing bending or cracking and other damage. The safety head provides a relief path or vent so that the slug or high-pressure gas doesn’t push directly against the valve plates, reducing the impact forces and preventing valve plate damage.

This isn’t about overheating, electrical faults, or lubrication issues. Those problems come from heat load, wiring or motor faults, or lubrication failures, respectively, and are addressed by other parts of the system.