I think that you are probably blowing the ONE 15 amp circuit that runs the plugs in the unit along with other stuff. If this is a routine operation, I strongly suggest that you consider putting another breaker in your box and a plug for one of the heaters. It has been documented well on this forum that the 15 amp wall plug circuit is overloaded in many of our campers.
Just a suggestion.
2007 Chevy 2500HD Classic LBZ Duramax/Allison (Stock)
2005 Bigfoot 1500C8.2 AWESOME