Lance 815 shower bypass

Thanks Freelance (great name) what size was the ball valve you installed?

I tapped a street 90 into the side of the trap. Then I installed a ball valve. If I open the valve the water runs out to a garden hose and beyound. Close the valve and it goes back into the black tank. Once I made the mod I think I only closed it one time. There is no y or other plumbing on the 815. The shower dumps directly into the BLACK tank. I did all my work through the little access panel Kohldad refers to. You need to be carefull that trap is not a common part. Its actually a Lance part #. The only place I could find one was from Lance. I went all over Elkhart In looking no luck.
Good luck

Under the furnace on the bathroom wall, you will find a small access panel held in place with 4 screws. The drain goes into a trap, then over to the outside wall where the black tank vent pipe.

You can also work on it from the opening in the bottom of the camper.

Instead of trying to fit a Y in the pipe, I just capped the trap to seal the black tank, then I adapted the drain to a small 1/2" hose barb. Connected a hose and ran it to the back of the camper with a couple feet extra. At the end is a ball valve so it doesn't drain until I'm ready. When we take a shower, we just catch the water a bucket. Then we have the choice of dumping it back into the black tank, the gray tank, or campground disposal area.

Works for us because the TC shower has been our backup. we usually stop in a campground with decent showers ever third or fourth day and use it.

I just hope that there is a short pipe that I can install the Y fitting on before the drain goes into the holding tank. I thought the drain went directly into the holding tank.

There are several ways to get the "Y" in there. Gray water is much easier to plumb than black.

Thanks a lot red. If I can fit that directional Y in there I can picture exactly what you mean. I really appreciate your help on this.

As I understand your question, you can install a bypass valve if you have the
Welcome to the RV.NET Forum

If I understand, you can split the gray water from the holding tank if you have the space for the plumbing. Simply stated, you have to disconnect your gray plumbing from your holding tank. Install a "Y", with a directional valve, or two gray dump valves. Probably easiest with the two gray dump valves. Connect one of the dump valves to the holding tank. Add a dump connector to the second gray dump valve. Ideally, the gray dump valves will be higher than your holding tank. This will prevent back flow if you open the gray dump valve to dump connector without closing the gray dump valve to the black tank first.

Wayne