Below is a photo of the flush fittings on my holding tanks (96 coach). I always thought that inside the tanks was some sort of pipe with holes that would do a good job of rinsing the tanks. After looking at these fittings they may just spray water out the other side. Anyone know what for sure what is there? They do have a check valve so that nothing flows backwards through the fitting.
I don't know what type of spray head they have inside the tank, but I do know that mine does not have a check valve. I had a little drain out of my grey tank when it was full one time.
Our '89 came with a spinner head (that did NOT spin) that someone had fixed so it wouldn't spin. I purchased a new one and put it in myself. Quite easy, with a check valve included with the purchase. I can hear the spinner going when I attach the hose and turn on the water.
Does it work? Seems to but the bottom sensor in the black tank almost always indicates 1/4 full for quite a while until the sensor dries off.
Keep in mind our coach is 30 years old and the sensors still work. I have done a complete, thorough flush at a dump station, came home and then filled the black tank full. I then ran the water out on our east lawn and got nothing but a small piece of "scale" that looked as if it had spent years on the tank wall.
Would I install a flush/spinner again?? Darn right, seeing as how the tank sensors have indicated empty now for the 7-8 years we have had the coach.
I like Norm have one each black and grey.. with a Y connection.... easy to switch between.
Backflow? Positive water pressure prevents this... Well for that to happen, must full tank, water off at the source and an air leak somewhere else in order to create a siphon..
I try to use an air gap at the supply side of the hose, therein never have to worry about contaminating the water source. Yes it is possible to contaminate your water hose
I took mine out to clean them. They are nothing more than a piece of capped off plastic pipe about 6" long drilled with a bunch of holes. Nothing spins or was meant to.
Thanks everyone, looks like it could be a spinner or pipe. Not sure if I want to remove the fitting to find out. I always put some water in the black tank after I dump. I let it run for about 2-3 min and hope that is about 10 gal. I can usually get by without chemicals between dumps unless it is really hot weather.