There are four wires on the NoCold POS recall box which is up to Revision F. Only the later versions will reset with a magnet. Two of the wires are larger than the other two... they are the power in and power out (probably blue) wires. Take the other large wire and plug it in where the blue wire is connected to the control board.
Since the recall box stopped working while the refer has been turned off it's not likely to be a leak, BUT look for any yellow stuff around the flue and an ammonia smell.