Originally Posted by bubbles
You seem a little confused. The water pump does not pressurize the potable water tank it pumps water from the tank. Maybe now it makes more sense.
Some RV's have an external shower, or external hose connection that is part of the "normal" plumbing ... it's just like another water faucet.
In our case, it has a hot and cold knob, and comes out to the absurd fitting that you plug a blue spiral hose into. Other people might have a shower head, or a garden hose type fitting.
So we just TEMPORARILY
connect that hose into the receptacle for the black tank flush device.
- although there is (usually) a vacuum breaker / anti siphon device on those black tank flushers (installed at factory) it is still important to never connect and leave in place, that hose back to your potable water system.
In another post, we put a picture of what the "interface" (Forest River / Tracer calls it a "Docking Station") looks like on their contemporary models ...
Link -> Newbie
(link name is thread name only, NOT labelling anyone.)
The blue hose plugs into the "faucet" where the pink tag is hanging. That is just a hot/cold water tap, pressurized by either internal pump when turned on or city water when connected to same. The other end of the blue hose has a regular "garden hose" connector and that screws into the "Black Tank Flush" receptacle.
We actually put an "On-Off" shutoff on between the garden hose thread and the tank flush receptacle, and close it before we turn off the water pressure at the hot/cold knobs. When we disconnect about a half cup of water runs out of the receptacle and stops, which proves there is a vacuum breaker / anti siphon behind it - but not everyone should presume that is there. And we still disconnect it EXCEPT when in use.
If we could find the obnoxious little fitting then we would make up a dedicated hose for this purpose only. So far have stumped our dealer and a lot of parts places.