Black Tank Flush

[NEO noob]

Hello all,
While de-winterizing our new TT (2018 Vibe Xtreme Lite 227RLS), I decided to try the black tank flush feature. Hooked up water hose from garage to the BWT connection and opened the garage faucet valve. No water flow sounds coming from the potty on the inside and no water draining from the BWT dump connection. I did have a Camco brass water regulator hooked into the system (pictured). Would anyone suggest removing the regulator? Maybe not enough pressure to operate the BWT Flush/rinse system?
Also, found the water drain on the underbelly easy enough but no sign of a hot or cold drain. Would it be possible that there is no hot or cold water drain installed on my model?

Many thanks for advice/suggestions.

[Kimber45]

I have been told that the black flush is an orbital spray head. Should work under any pressure. I'm assuming its clearly marked and you weren't hooked to city water? My hot and cold low point drains are no were near my fresh tank drain. they area clear on the opposite side.

[andymil]

The low point drains can be hard to see without laying under the trailer. The ones on our 2703WS were so close to the skirt you had to lay under it to see them.

The anti-siphon valve in the black tank flush line has a check valve built in and has been known to be installed backwards at the factory.

[NEO noob]

Thanks andymil.
Reading a few other posts, I’ve read where the anti-siphon valve has been reported to have been installed backwards. I spent some time looking for this valve. Opened panels under the sink and under the shower, no luck. Even had a look directly downstream of where the outside BWT Flush hose connection point is. Nothing there, either. If anyone has had success in locating their anti-siphon valve, please advise.
Many thanks,

[Scrapper]

Sometimes the anti-siphon valve is hidden up behind the sink bowl, not where you can plainly see it. Some are installed higher than the toilet bowl.

[andymil]

Yeah, mine is under the bathroom sink.

[NEO noob]

After a thorough search, I found the Anti-Siphon Valve under the kitchen sink cabinet up against the refrigerator. Of course, the lines were backwards. Swapped the connection and the Black Tank Flush works fine, now.
A little disappointed - where is the Quality Control process during manufacture of these trailers?
After reading several posts on the subject, it seems that this is a common problem. Certainly more common than it should be...

[andymil]

Quality Control???

Sorry, I couldn’t help myself. I’m glad you fixed it.