The accumulator is a very important component in heat pumps and low temperature refrigeration equipment. It is a vessel that collects any liquid refrigerant that is not boiled off in the evaporator. This prevents the compressor from slugging, (trying to compress a liquid) and causing major damage. In some extreme cases, a pipe-heater tape is wrapped around the accumulator and insulated. This ensures the refrigerant will boil sufficiently and enter the compressor as a vapor. Figure 12-2 is a typical accumulator showing how it works. This component is mounted in the suction line just before the compressor.