[astrungis]

Well, I bought a couple of 90 degree "shark bite" elbows at HD and removed the back flow preventer under the bathroom sink. Now I am going to buy a in-line hose back flow preventer in the convenience center. BTW, I use the outside cold shower valve and the coiled blue hose and connect it to the black tank flush since we never use the outside shower. At this spot, I will install the in-line back flow preventer. Thanks to everyone!