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Knowharm's avatar
Knowharm
Explorer
Apr 12, 2019

Strong sweetish odor

Hi. Please help. I have searched the internet and could not find my exact question posted. First time in an rv. Rv toilet had the very faint typical rv sewage smell when we started trip 2 days ago. Today my wife “had to hold the flush valve open and let it run for a really long time” ;)
But now there is a disgusting, sort of sweet smell, not quite like anti freeze, coming from the toilet and is permeating if I turn vent off.
Does anyone know what this odor may be and what I can do to kill it?
Thanks for any help!
Class C

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  • bobndot's avatar
    bobndot
    Explorer III
    Apr 12, 2019
    once you resolve this. use the tanks properly and flush them both using water to keep them clean.

    check your plumbing, make sure your vent to the roof is not blocked, open the end cap and take a peek down the tube to see if it appears clear, not blocked by something.

    try the Geo Method to clean the tanks. read below rvnet post for link to instructions. Once its clean, many people simply use water to keep things clean.

    https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/27808130/print/true.cfm
  • gbopp's avatar
    gbopp
    Explorer
    Apr 12, 2019
    Welcome to the forum.
    Did you dump and flush the black tank? It sounds like it may have RV antifreeze in the tank.
    I would rinse the black and grey tank.

    Also, give us the make/model of your RV. Maybe someone had a similar problem.
    If there is RV antifreeze in the tanks, another possible problem could be a stuck air admittance valve.

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