Sewer backflush mod

[Myyke]

I added a valve from my cold water line under bathroom sink to my sewer backflush, so i could use either city water connection or water pump to flush sewer tanks. Backflush connector on my trailer didn't have a check valve, so i plugged it for now, until i decide to change it out to a connector with a check valve.

[GaryWT]

I hope it works out for you but the last thing I would ever do is cross the fresh water system with the black water system. Seems like some type of code violation even if a check valve is used. What a mess it would be if sewer ever got into the fresh water. I am sure it will be fine but it would worry me.

[Myyke]

I checked, and there is a vent (just below top lip of sink) between backflush and valve, plus water would have to overflow back through tub sewer before it would get that high to get back to valve.

[Myyke]

Just checked the vent under sink for it, and it has a check valve built in on mine, so no worries there.

[MarkS]

X2 on the worry!


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[SteveC7010]

Originally Posted by GaryWT

I hope it works out for you but the last thing I would ever do is cross the fresh water system with the black water system. Seems like some type of code violation even if a check valve is used. What a mess it would be if sewer ever got into the fresh water. I am sure it will be fine but it would worry me.

Especially given the reported high failure rates of the vacuum breaker, I fully agree with your assessment, Gary.

My Cougar has the outdoor shower right next to the fresh water inlet and the black flush inlet. I can add an extra anti-siphon on the end of the curly blue hose and connect to the black flush if needed. No mod required, no chance of failure or other troubles when not connected. I've only done it a couple of times in campgrounds with no garden hose fitting on the end of their water hose at the dump station. And then, just long enough to dump, flush, dump and go.

Risky business IMHO, but to each his own.

[rlevitt]

I would never couple the fresh water and a black water together even with a check valve.
I also would not use my fresh water hose to flush the black tank. Those nasty critters in there seem to move about and not worth getting sick.
Just my opinion.
Ron