Which device is used to prevent refrigerant overfill in some systems?

Which device is used to prevent refrigerant overfill in some systems?

• A. Flow switch
• B. Float switch
• C. Pressure switch
• D. Temperature switch

Answer: (B)

Preventing refrigerant overfill relies on detecting the actual liquid level and stopping input at a set point. A float switch does exactly that: a buoyant float sits on the liquid surface and rises with the level. When the float reaches the preset level, the switch changes state and stops the flow or tripping a valve, preventing any more refrigerant from entering. This direct level sensing is what makes it suitable for avoiding overfill in systems with storage or charging vessels. The other devices monitor things other than liquid level: a flow switch checks that refrigerant is moving through the line, not how full a vessel is; a pressure switch guards against unsafe pressures by controlling the compressor or other components; a temperature switch responds to temperature changes, not the amount of liquid present.

Preventing refrigerant overfill relies on detecting the actual liquid level and stopping input at a set point. A float switch does exactly that: a buoyant float sits on the liquid surface and rises with the level. When the float reaches the preset level, the switch changes state and stops the flow or tripping a valve, preventing any more refrigerant from entering. This direct level sensing is what makes it suitable for avoiding overfill in systems with storage or charging vessels.

The other devices monitor things other than liquid level: a flow switch checks that refrigerant is moving through the line, not how full a vessel is; a pressure switch guards against unsafe pressures by controlling the compressor or other components; a temperature switch responds to temperature changes, not the amount of liquid present.