Water drain?

[jornvango]

In the empty space underneath a closet (the closet in between the kitchen and the bathroom in our 95 Sovereign), there is the following piping: see attached image.

When placing a cardboard box in there, we accidentally had the box turn some of the knobs on the piping.
It resulted in the bathroom faucets no longer working and in water spilling out of 2 small pipes (tubes) sticking out from under our water tank underneath the trailer.

Turning the knobs back made the faucets work again.

Any idea what I'm looking at here?

Thanks.

[Belegedhel]

These are likely to be valves installed so that you can drain all the water out of your waterlines for "winterization." If you look around the trailer, you should find a few more such valves. The idea is that when the temperatures start getting cooler, you drain all tanks, and open up these valves, and take a spin around the block, and all of the water ought to drain out of the system.

[jornvango]

Thanks!