2005 Greyhawk 24SS: water lines that do a U-turn in the wall

[Eric6A]

There are two water lines, side by side about 4" apart, that go up inside the wall between the kitchen sink and the shower. About 4 feet up, they join together with a fitting - basically, a U-turn in the wall! One line comes from the left side and behind the tub; the other seems to also come from the left side, but in front of the tub.

Does anyone have any idea what these lines are for? I think they are cold water lines, as they don't have any markings on them, and the hot water lines are labeled with temperature and psi ratings.

[moonraker1]

If you have a black water wash outlet . Its done that way so it drains out so it wont freeze in the winter

[Eric6A]

Wow, I'm glad I asked, because I never would have thought of that! It does have the black tank rinse, and I'm glad I didn't try to tap into the line for water I needed for the Turbokool cooler.

I now see there is an 18" long section of the cold water PEX line to the sink with hand fittings on each end. I'll remove that so it's easy to install the Flair-it tee fitting for the Turbokool water, run the 1/4" tubing to my shutoff valve, and I'm finally done.