PREVENTION OF REFRIGERANT SOLIDIFICATION

摘要

A refrigerant system may utilize CO<SUB>2</SUB> as a refrigerant. Should the sensed operating conditions indicate that the refrigerant might be approaching a condition at which the refrigerant could solidify, corrective actions are taken to prevent refrigerant transformation to a solid thermodynamic state. In one embodiment, hot gas from a compressor discharge is bypassed to a location upstream of the evaporator. In another embodiment, the high-side pressure of a refrigerant system is adjusted. In yet another embodiment, an additional charge of refrigerant is delivered on demand into the refrigerant system. In still another embodiment, a defrost cycle is initiated on demand. These embodiments prevent the refrigerant from approaching the conditions at which it may solidify.