DrewE wrote:
... If you set the system up for winterization and open the valve to fill the RV tank from city water, ...
I don't have an accessible valve for filling the freshwater tank from city water. I just have on outside hose fitting for this.
There must be a one-way valve inline with this outside hose fitting - or something similar - to route water to the tank from this outside hose fitting whenever water under pressure (from a hose) is attached to it while at the same time preventing pressurized water from the water pump system ever coming out this hose fitting.
I think the way that the built-in winterization system works is it routes fluid that the water pump picks up - from a container I supply - into all of the plumbing in the RV except for the freshwater tank itself ... because the freshwater tank itself can be completely emptied via a valve in it's drain pipe to the outside. If I'm right about this, then why can't the water pump also be used to pick up potable water from a container inside the RV that I supply and then pressurize the internal plumbing system with this new potable water - which includes the outside shower plumbing that is near the fresh water tank's gravity filling outlet? Hence, then, add this water to the fresh water tank - conveniently using the outside shower until my container of backup potable water is empty?
I'm just trying to use our RV's existing pump and built-in plumbing to refill the fresh water tank from a heavy container carried inside the coach when drycamping - without designing, buying, and rigging up additional 12V pumps, tubing, and containers to accomplish the same thing - or without having to carry a heavy container outside, lifting it up to the gravity fill port, and then holding it up there until it's emptied into the fresh water tank. I try use the RV's systems in as many multiple ways as possible to keep things simple, convenient, and inexpensive.