I have been working on this unit for some time changed the defrost board , replaced the low pressure switch , added and removed charge . I replaced the pressure switch and resolved one fault code and then with I an half hour of opperation I gotanther fault code that said I was( reciving a single on w in the a/c mode) but we were in the heating mode ..... I checked the wires no short now Im going to replace the t-stat.. anyone with crazy **** like this like to know thanks