Hello All, My air cond will not work at all in the camper, it's a Duo Therm model 58915.302 with a Dometic 3109228.001 thermostat. The thermostat will not power up, what can i check for to see if i can get this unit running? Its a older model camper , 1990 Flight Leader in pretty good shape. I dont know if this is the orginal air cond or not. Any help would be a big plus!