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Old 10-05-2016, 06:58 PM   #21
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Re: Black flush every time?

Originally Posted by poppin_fresh View Post
If you wanted, you could do away with the back flow preventor and the regulator. The black tank flush already has a back flow prevention built in and the regulator might actually be reducing your ability to spray the tank as clean as it could be.

You actually want high water pressure to do a good job of spraying stuff in the tank. Since you cant shut off the water flow, there is no "pressure" on the plumbing components of the tank flusher so high water pressure is of little concern.
I've thought of that, but one place I frequent has 100 psi water pressure and I'm reluctant to test the theory.

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Old 10-05-2016, 07:42 PM   #22
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Re: Black flush every time?

There are two types of black tank nozzles. One is a stationary nozzle with several holes that spray water in a random pattern. The other is a rotary nozzle with two/four holes (depending on model). That type spins and sprays water in a circular pattern. Either one is effective to cover the inside of the tank. The rotary nozzle needs water pressure around 40 PSI to operate effectively, but any significantly higher pressure runs the risk of "overspeeding" the nozzle and damaging it. I've seen several that were "twisted off" or "blown off" of the fixture. I would guess (although I've never seen it) that the ones with stationary nozzles would also restrict water flow through those small holes and eventually build up enough pressure to potentially cause damage.

Somewhere a few years ago I was reading the installation instructions on an "add on" black tank flush in a Camping World. It was the type with the rotary nozzle, clear hose and "under rail" connection for your garden hose. The operating instructions indicated that the unit was designed to operate at a minimum of 40 PSI and cautioned not to exceed 60 PSI.

So, I've always used my water regulator with the black tank flush. I've seen campground water supplies that exceed 100 PSI at the "low pressure sites" and upwards of 120 PSI at those closer to the street where the campground tied into the city water supply.


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Old 10-05-2016, 08:36 PM   #23
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Re: Black flush every time?

Come on guys!!! It's a holding tank not a fresh water tank. Most people find they hardly ever have to back flush. Once a season? Sure. Seriously you have no need to get that tank clear water clean every time you camp. You are just making work for yourself. And I would never hold up a line at a park so I can do that.

We use our trailer almost every month and for a couple months full-time in the summer. I back flush once a year. Never in the summer when we are living in it. For those winter trips, I drain, put a couple gallons and some Happy Camper back in it and am ready for the next trip. Never smells, everything drains. Why make so much work for yourself?

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Old 10-08-2016, 04:28 AM   #24
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Re: Black flush every time?

I backwash both tanks after every trip. My wife has a very sensitive nose and she says she can smell the difference if it`s not washed out. I`ve found that if I don`t backwash the black tank, I get these little flies inside the tank. I`m not sure how they get in there, but when you step on the pedal to open the seal, they fly every where inside the bathroom.
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Old 10-08-2016, 04:33 PM   #25
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Re: Black flush every time?

I am with Treeyers,been camping 40+ years never had a backflush and not had any problems.
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Old 10-10-2016, 10:28 AM   #26
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Re: Black flush every time?

I use mine every time all the time
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Old 10-17-2016, 05:56 PM   #27
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Re: Black flush every time?

I flush mine every time i dump every other week we're seasonal so our trailer doesn't move unless we take a trip which is usually once a year.
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Old 01-28-2017, 07:27 AM   #28
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I go with "once a year" at end of season. I also use some water softener (found in the laundry aisle), and ALWAYS put a bit of that in to start (tank empty), and will put a little water in before "anything else" goes in the black tank.

I've found that the water softener seems to do wonders for helping to move things along when you dump it.
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Old 01-28-2017, 07:41 AM   #29
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Having worked on units that the owner has flushed and some that have not...I prefer the flushed ones for obvious reasons.

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Old 01-28-2017, 09:01 AM   #30
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I found recently that if I lower the front on my 2810 a little I will get more out of my black tank, even after having flushed it a lot.

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