In my 72 31 footer the copper starts in the left rear, (facing front at back of trailer) loops around to the right, going under the tub, through the closet, under the bed, then comes out under the edge of the kitchen cabinets, and under the kitchen sink, to the water pump. There is a second loop and return from the left side coming from the hot water tank, next to the toilet, with a T on the cold side of the HWT for the toilet. I had two bursts in my copper when I bought it, one under the tub, and the other just 1 foot to the right of the pressure regulator. I had to take out the storage shelf first. I cut the burst section of copper out and replaced it with high pressure black hose and stainless steel hose clamps. If you wanted to replace the copper, assuming a burst under the tub, you could cut it either under the bed, or closet, near the Univolt, and in the storage compartment in the rear of the trailer and fish some new copper in, or use high pressure black hose. I know you can do this without removing the tub. Take the door off in the closet where the Univolt is and look in there, you will see the hot and cold lines under the tub. If you do use black hose, be sure it is the right size, or it will slip off. I had to heat mine up before it would slide over the copper, and it fits very snug.
2003 GMC 2500HD 4X4 D/A Ext. Cab
Propane Powered Honda EU2000i
Lots of Hot Sauce!
Air # 283