What device prevents slugging in a heat pump?

The accumulator is the device that prevents slugging in a heat pump. Slugging occurs when liquid refrigerant enters the compressor, which is designed to handle gas rather than liquid. If liquid refrigerant reaches the compressor, it can cause damage to the unit, leading to costly repairs or failure.

The accumulator functions as a storage device that allows any excess liquid refrigerant to be held temporarily before it is evaporated and sent to the compressor as a gas. This is particularly important during low-load conditions where liquid refrigerant may not be fully vaporized. By ensuring that only vapor enters the compressor, the accumulator helps maintain the efficiency and longevity of the heat pump system.

In contrast, the evaporator is responsible for absorbing heat and turning the refrigerant from a liquid state into a gas, but it does not prevent slugging. The compressor's main function is to compress refrigerant vapor to higher pressures, not to manage liquid refrigerant. A drier, on the other hand, is primarily used to remove moisture from the refrigerant but does not address the prevention of slugging. Thus, the accumulator is essential in protecting the compressor and ensuring the system operates effectively without the risk of liquid refrigerant entering it.