I have a 2015 crossroads z1 301bh. Atwood water heater burst causing us to make a switch to a girard tankless water heater. My problem is the girard heater runs only in 12vdc. I have two sets of wires leading back that should in theory be 12vdc. However after attempting to hook up to them as soon as the switch comes on the power alters and no longer registers 12vdc and girard he rater does not come on. The two sets of wires are white and orange and the other set is black and white. Anyone actually know which is which for this purpose?