Flushing out your sewage tank EZ WAY

[Franswa]

well FK fine print says backflow preventer included alright.....but where is it??? I don't see it in the many pictures provided....

that IS a garden hose fitting on the end of that hose....and that black thing looks like just a simple 1/4 turn in-line valve to me.....can't see that being it (not enough room)

could be wrong...happens lots....

[Wallo]

I think the gate below the garden hose fitting is the backflow preventer. According to the Flush King description, "Flush King rapidly refills the holding tank no matter what height of tank or angles in plumbing. Unique design eliminates messy wands and hoses inside the RV by allowing you to reverse flush your tanks from the outside. " The water is prevented from flowing down the sewer hose until after the tank has been re-filled. When the tank has been refilled, or rinsed, the gate can be opened and the tank flushed again. Appears the purpose is to avoid running back and forth to the inside to add water to the tank for a 2nd flush.

[Evergreengirl]

To go back to the OP's picture and explanation. I'm not sure I completely understand your operation. Are you saying that after you've connected your sewer hose and dumped your black water tank, you then disconnect it and stick a garden hose up your vent pipe to flush the tank? Doesn't residual black water splash all over the dump station area? That wouldn't be very sanitary. Lot's of places wouldn't allow that practice. You must be connected directly from your black tank to the dump station's sewer opening via your big sewer hose. And how do you connect your garden hose? At most dump stations the hose for flushing your sewer hose does not have a garden hose type connection on the end of it. Usually there is no connection at all, just a piece of hose with a cut-off end. Or do you just stick the dump's hose up the vent? Either way I wouldn't recommend this type of procedure because of the chance of spraying black water all over the place. Of course, black water does get splashed around at dump stations but why risk adding to the problem and maybe getting it on yourself too?

I'm kinda in Franswa's camp on this. I've never quite understood the need to do all that flushing of black water tanks in the first place. Yes, if they're not maintained properly, "gunk" can build up in the tank, but treat 'em right and you won't have any problems. Dump your black water when it's at least half-full (fuller is better, run some water into your toilet if you need to). After you dump, run a little water into the toilet and add your preferred tank treatment and your good to go. The ice cube trick can work well too.

We also never drink from our fresh water tank. Mostly we don't like the off taste of the water from the tank. In some parts of the country, particularly in the SW, the water can be very alkaline and unpleasant to drink too. We rely on refillable jugs of water for drinking, filling them at campgrounds if we think the water is clean and good tasting, or at supermarkets where they have those filtered water machines. Some people use their own in-line filters, but that's just one more thing to deal with. We like to keep it simple.

[cpaharley2008]

The anti-siphon, backflow preventer is installed on the fresh water supply to prevent sewer contamination going into the fresh water supply hose at least that is what I have always thought?? They are installed on supply lines to tank rinsers.

[jazzjunkysue]

Franswa:
I sent that photo to everyone I know!

Never saw it before! Thanks!
Sue

[jazzjunkysue]

I don't know. I love the plain, old Rhinoflex. My lines are separate, too. There's a $7 rinser I attach to the dump fresh water hose to rinse out the 3". No smell at all. The whole system, with the extra clear 90 degree clear elbow was $40. Those fancy gadgets are more than double that. And they're slow. Mine's so quick. I actually fill and empty 3 times and it's fast.

Don't see why I'd ever need anything else.

[Timber Wolf]

Originally Posted by Evergreengirl

We also never drink from our fresh water tank.

Off topic but "ditto". We have only been on week-long trips max so far but have no trouble keeping plenty of drinking & cooking water in milk jugs filled and brought from home.