liquid solvent in the storage 20 at a predetermined temperature to minimize the vaporization therein the system is best seen in fig2 and operates to cool the storage tank under all portions of the cycle except the drying portion thus the description for stand by includes these other portions of the cycle thus whenever the thermostat 141 within the tank 20 exceeds a predetermined limit 80 u00b0 f the refrigeration unit is energized with cooling directed to the evaporator coil 144 in the storage tank 20 in the system shown the refrigerant flow path includes a compressor 146 with a compressed refrigerant directed therefrom through line 148 to refrigerant condenser 150 accumulator 152 filter 154 and sight glass 156 to t connector 158 of the two lines 160 and 162 leading from the t connector 158 line 160 contains a normally closed valve 164 which thus prevents flow therethrough however line 162 contains a normally open valve 166 permitting the refrigerant to flow into line 168 leading to expansion valve 170 and evaporator coils 144 in the storage tank 20 from there the refrigerant is directed back to the compressor 146 through line 172 and t connector 174 once the solvent in the tank has been cooled to around 75 u00b0 f the refrigeration system is deenergized but ready to repeat the cycle whenever the temperature exceeds 80 u00b0 f during the dry portion of the cleaning cycle the refrigeration unit is continuously energized through a switch 143 see fig4 controlled by the timer at this time the refrigerant flow from the compressor 146 is identical to that described above until it reaches the t connector.