Factory installed black tank flush

I use compressed air and blow it out. Don't know if it self drains, didn't want to take the chance.

AVid

I take a length of hose, about 3 feet, connect it to the camper, then pour anti-freeze into the hose and then use my compressor to blow it onto the lines. Use a funnel, or else you get it everywhere......

I have never done anything with it and have had no problems. I think that it drains pretty well since it is open on both ends.

Me either.

Mopar,

The black tank flush has a back-flow preventer valve. In mine its located in the wall between the WC and the bedroom (has a little 6"X6" cover over it). When I shut the water off after a flush, the water on the inlet side of the BF Preventer drains back out onto the ground and, if its working properly, the water on the Black Water tank side of the Preventer drains into the tank. I can actually watch the water flow back out of the hose side of the line by watching the BFP supply line that's attached to the ceiling of the basement. Like Avid though, I too blow some compressed air into the line to get any residual water out of the valve itself and any that might be left in the line on the tank side of the valve.

What PSI are you guys running when you blow out the black tank flush line?

Freedom1955 wrote:What PSI are you guys running when you blow out the black tank flush line?

40-50psi. The water pressure reducer that most of us have will work with air pressure also. By definition, air is a fluid too.

One reason I always blow the system out is because the water inlet line between the inlet and the pump will not fill with anti-freeze when you winterize the unit. The pump draws in the anti-freeze but unless you push in the inlet check valve, the anti- freeze won't go up the tube, only into the units plumbing system. I don't like manually depressing the check valve because too many times they never go back into place and have to be replaced.

AVid

I winterized today. Blew some air through the black tank flush and got a little water out.