Hi Nancy
I had this problem.#1--make sure no
leaks can get into rv from exterior of hot water tank.When i took hotwater cover down there was a small acess hole for
propane line and the rubber seal was shot.We just put caulking in hole around
propane line.
#2--I had my lines inspected this spring and found a second source for
propane smell.We had a broken flange where two lines joined and it was covered with black tape.Now repaired properly.
Hope this helps