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"Sonic Flushers" in the service bay.

April 16, 2013, 08:08:54 pm

I'm about ready to tackle the service bay to clean it up and learn more about its operation.

These two Sonic Flusher's nipples under the faucet -- I'm assuming you hook-up an external water hose to them, and maybe there is a venturi in the line that causes a agitating wave to help flush the black and grey tanks with the dump gate valves open?

Also pictured is what looks like a in-line filter to be used when filling the fresh water tank, but all the labels are worn off of it. Not that I would use this one, but just trying to confirm its purpose.

As mentioned in my other post about getting the Audit system back up the other day, the black tank reads 25% (the others -- empty). That fill-level, if accurate -- could have been in there for years now. I might have a "constipation" issue ;-)

By the way, the hose hook-up the way you see it there in the picture was as it was when I got the Coach.

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Re: "Sonic Flushers" in the service bay.

Reply #1 – April 16, 2013, 08:18:55 pm

Michael,

I put brass quick connects on the flush connections and keep a grey hose with the other end on it as it makes flushing much easier.  I also have a gun type hose end so I can connect that to wash down.  I use the grey hose only for the flushing to prevent contamination of the fresh water tank.

The tank may be reading 25% as the lower sensor is covered with paper or something.  Flush the tank really well or try putting water softner crystals and a little detergent  in the tank and fill it 3/4 full and go for a drive.


Keith

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Re: "Sonic Flushers" in the service bay.

Reply #2 – April 16, 2013, 10:35:55 pm

You should be able to open the flush ball valve and look straight down into the tank to see if it is empty. If not and the black tank won't empty out as usual, partially fill the gray water tank, leave the cap on the dump outlet and open the gray water valve then the black water valve. The gray water will back flush the black tank. Be sure to close the black  and gray water valves before opening the cap cause stuff will run out. Also be sure not to over fill the black tank once the blockage breaks loose. Keep an eye on the black tank level through the toilet.

If you don't hear the gray water rushing into the black tank, let the water set for a while to soften the blockage. Again, remember the gray water tank is almost twice as large as the black tank. Don't overfill the gray water tank.

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Re: "Sonic Flushers" in the service bay.

Reply #3 – April 16, 2013, 11:35:45 pm

I normally dump black first usually with the coach tilted. After the black empties I leave the black open hold the hose up a couple feet and open the grey and let some flow into the black then close the grey lower the hose and repete a couple times. Works for me.

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Re: "Sonic Flushers" in the service bay.

Reply #4 – April 17, 2013, 07:34:52 am

I've used Phil's flushing approach for years and find it very effective, but I suspect Michael's problem is most likely to be bad black tank sensors.  The originals have proven very unreliable.  I've switched to the SensaTank system, which uses the original coach wiring.

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