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JimNH's avatar
JimNH
Explorer
Jul 14, 2015

black tank odors after storage

we have a small hybrid TT with small tanks - a "weekender" really.

Last time we were at a site with full hook ups (which was fortunate, since I got some kind of stomach bug and took full advantage...)

This time we are back at Chocorua with no sewer hook up. Everything went fine for set up, but we have some black tank odor to deal with. We added more water to the tank and one of the one-time use enzyme balls, and that has helped.

I think the issue was maybe not adding water after emptying the tank last time, and the smell occurred while the trailer was sitting in the driveway in the hot sun for a week or more.

My plan (we're home today during the day, heading back up late tonight or early tomorrow) is to get a flushing wand and hose, and clean the tank then dump into my portable tank, then fill with a few gallons of water and some enzyme.

Sound right?

JIM in NH

18 Replies

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  • Lynnmor's avatar
    Lynnmor
    Explorer
    Jul 15, 2015
    I use the chemicals since odor may come up the toilet when flushing and there is less stink when dumping. Use several gallons of water at the start since just one gallon will all be in the drain pipe.

    If you think that any flush system will completely clean the tank, try this: After flushing, add a few gallons of water and drive to the next place you can dump without using the toilet. Using a clear elbow, dump the tank and observe the brown trout swimming downstream.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Jul 15, 2015
    I don't use ANY chemicals and NO smells cause all vapor barriers work.

    Stink inside (other than when flushing toilet) is due to something not working .

    All the chemicals will NOT cure that problem......just have a chemical smell inside
  • Dick_B's avatar
    Dick_B
    Explorer
    Jul 14, 2015
    I think the Flush King or Hydro Flush is a better approach than dragging a hose thru the camper to flush out the toilet tank then dragging the potentially dirty want back thru the RV. Keeps all the `black' stuff out where it belongs.
    There is a video showing the Hydro Flush cleans the tank better than my No Fuss Flush ie. built-in flushing system. Hard to believe but the video proves it.
  • JimNH's avatar
    JimNH
    Explorer
    Jul 14, 2015
    Thanks. Off to the RV store for some Aqua Chem Dri I guess...

    I also plan to check the vent stack up on the roof - just to be sure.

    JIM
  • the_bear_II's avatar
    the_bear_II
    Explorer
    Jul 14, 2015
    After dumping the black tank and closing the dump valve I always use a packet of Thetford Aqua Chem Dri mixed in a gallon of water. I dump it down the toilet and let it slosh around as we head back home.

    There's never a bad smell even if the trailer has been stored for months.
  • llowllms's avatar
    llowllms
    Explorer
    Jul 14, 2015
    I use a flush king to back flush the black tank until it runs clear, add 1gal of water after rinsing and liquid rv toilet chemical purchased at Wal Mart. Never have odor issues.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Jul 14, 2015
    Well.......
    That won't hurt to clean tank

    BUT real question is WHY you smell ANYTHING inside the trailer????


    Does toilet bowl hold water?
    Is toilet floor flange not sealing?

    Grey tank can smell as bad as a black tank (body oils, hair, food particles etc)
    Are the sink/shower 'P' traps holding water?
    Is the Air Admittance Valve(s) under sinks closing?

    You see.....all of the above are vapor barriers that keep waste tank smells out of inside of RVs

    So find source that is allowing smell inside and cure that problem.

    Make sure 'P' traps have water and then pour some veg. oil on top of water.....for storage/periods of non use. Keeps water from evaporating.
    Same for toilet bowl.

    I use olive oil. Keeps toilet bowl seal lubed also.

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