rk911 wrote:
I always do. those tanks are never really empty. same with the WH bypass. and I slowly pour a small amount in each drain for the p-trap along with a moderate amount in the john to keep the blade seal moist.
That's what we always did, too.
Another thought: if your vent pipe is open at the top, rain can get into the tank after you drain it; and then freeze and break the pipe. And lastly - some RVs simply don't completely drain. Our previous 5er was awful about retaining water (and had the freeze-cracked drain lines to prove it)
