Black tank flush

[Cougar25rds]

Hi everyone I just got a new 2023 keystone 25rds and having problems with the black tank flush not accepting a water for the hose. I called for warranty but they said two months away, so if I can fix it I will.

[chuckster57]

Welcome to the forum

I take it you hook up the hose and water doesn’t flow?

Could be a faulty anti siphon valve, it may be installed backwards, or there may be a kink in the line. The anti siphon valve is commonly located under the bathroom sink, high in the cabinet. It will be marked for direction of flow, and you can verify that using low air pressure after taking it out.

[dutchmensport]

I agree with chuckster above, probably a backwards install anti siphon valve found under your bathroom sink. Here's a link from these forums threads that has a good photo of what you are looking for and some more information.

Good luck, click here

and oh!.....

Welcome to the forums, congrats on getting your new camper, and Happy camping!

[kohi30]

I have the same issue on my 2022 Alpine. The service techs found crushed water lines to the black tanks. Keystone sent out some hokey Valterra connector and clear tube to direct connect and I refused the repair and told the shop to have them replace the lines to allow the original water connections to be utilized.

[Cougar25rds]

I found the anti siphon valve under the bathroom sink and flipped it around and now it’s working.
Thank you to everyone for helping.