Hi, I have just purchased a vauxhall rascal chiller / freezer van. The van is fitted with a 'sanden' 12v unit model No.YCU 318LN9, refrigerant 502. Is it possible to fit the van with a 240v mains supply for overnight freeze as well as keeping the 12v for day us. I am looking for the easiest option. I would appreciate any feedback. Thanks