Got some more info on the heated plumbing bays. On my coach there are really two of them one on the drivers side and one on the passenger side. The plumbing bay on the driver's side has both Aquahot and electric heat and the bay on the passenger's side has just electric heat. After driving down the road in 15 degree external temps I stopped at a truck stop to see if the plumbing bays were warm. With heat not selected on the plumbing bay on the driver's side was toasty warm. Fetherlite confirms that this is as Jon said hot engine coolant circulates around the aquahot even though it is not selected on. The passenger side plumbing bay was another story, it was pretty cold. I went a head and let some water go through the low point drain over there to make sure no freezing had occurred and then selected electric plumbing bay heat for the rest of the trip. Featherlite had said that I did not need to have plumbing bay heat on whilst traveling down the road but I wanted to err on the side of caution. Now if the shop can just fix my damn air leaks! Thanks for the info everyone. Cheers