I recently purchased a used XMT 304, I tested it before I bought it and all the functions worked. The welder sat for 2 months while I rewired the garage for the welders power requirements. I tried to use it over the weekend, the welder turned on without any error codes but I couldn't adjust the current or the voltage. I set the operation to "Stick" and tried to adjust the current but digital readout was unresponsive and displaying erratic numbers for volts and amperes. Even when I wasn't making adjustments the digital readout was behaving erratically displaying random numbers. When I tried to strike an arc there was nothing. I know there is a serious problem but is it a problem with the board?