Forum Discussion

mtofell1's avatar
mtofell1
Explorer
Apr 22, 2016

VERY strong sewer odor

2016 Keystone Hideout, 2 months old. I've used it twice for a couple days each time and emptied the tanks each time and filled with chemicals and a couple gallons of water. In preparation for leaving tomorrow I went out and flushed the toilet and was overtaken by a ridiculously strong black tank odor. It was so "gassy" I felt like it would explode if I lit a match.

I understand all about plumbing and traps and this is my 5th RV. I visually looked at all sink traps and verified they are holding water. While the odor does seem to be strongest at the fixtures it's kind of just all over. Honestly, it's tough to tell where it's coming from (other than the black tank, of course :)) I'm suspicious of a detached vent pipe in the wall. Does this ever happen? How would anyone find it?

I added another bag of chemicals and another gallon or so of water and will recheck in the morning. I'm 99.99% sure I put chemicals in after last draining but I suppose I could have forgotten - new trailer, new routines, etc. but I really don't think I did.

Has anyone experienced anything like this before?
  • csamayfield55x's avatar
    csamayfield55x
    Explorer
    Apr 22, 2016
    Black tanks are vented through the roof. Make sure your roof vent is clear. I would also double up on chems next time and use LOTS AND LOTS of water. I usually fil lthe black tank to at least 1/3rd full before ever using it. More water the better. It is very hard to fill unless you areout for long periods of time

    Chris
  • bob213's avatar
    bob213
    Explorer
    Apr 22, 2016
    Grey tanks can smell as bad if not worse than black tanks especially a galley tank. Food particles in the grey tank breed bacteria that really smell. Try putting chemicals in your grey tank also. The warmer the weather, the worse the grey tank gets.
  • momentum_rv's avatar
    momentum_rv
    Explorer
    Apr 22, 2016
    If you have a black tank flush, you may have a stuck open vacuum break/check valve in the flusher line.

    As mentioned above it could be your gray tank. check AAV under sink. It may be stuck open.

    AAV = air admittance valve
  • TucsonJim's avatar
    TucsonJim
    Explorer II
    Apr 22, 2016
    momentum rv wrote:
    If you have a black tank flush, you may have a stuck open vacuum break/check valve in the flusher line.

    As mentioned above it could be your gray tank. check AAV under sink. It may be stuck open.

    AAV = air admittance valve


    I second the AAV under the sink. On my new rig, the AAV failed, and the whole rig reeked. A trip to Lowes and $25 later, the fix was in.

    Jim
  • mtofell1's avatar
    mtofell1
    Explorer
    Apr 22, 2016
    Thanks everyone - I went back out and did a bit more investigation. The smell really seems to be coming right from the toilet itself. The slide/seal it working and holds water and I looked all around and couldn't find anything out of the ordinary. It's been about 6 weeks since I parked it after the last use. It's possible one of my kids "used" it and won't admit it. Even so, I've had stinky black tanks before and isn't like this.

    I'm heading out tomorrow and will be at a full-hook site by evening. I'll dump, flush and clean everything the best I can and re-evaluate. I'll either be posting an update from the campground or the nearest Holiday Inn because there is no way the DW will sleep in the thing the way it smelled tonight :)
  • leeper's avatar
    leeper
    Explorer
    Apr 22, 2016
    When I read your post I heard that you went camping, used the toilet with no chemicals in it, then drained the tanks, and then you added chemicals after you where done using it. No wonder it stunk! You first put in the chemicals with water, then use it, then you drain the tank of the chemicals and what ever you put in the toilet! Chemicals first and not last when you are done. When you put the chemicals in with a little water and let it sit for several weeks the chemical lost its potency and things got stinky. Chemicals need to be renewed in order to keep working.
  • Learjet's avatar
    Learjet
    Explorer
    Apr 22, 2016
    leeper wrote:
    When I read your post I heard that you went camping, used the toilet with no chemicals in it, then drained the tanks, and then you added chemicals after you where done using it. No wonder it stunk! You first put in the chemicals with water, then use it, then you drain the tank of the chemicals and what ever you put in the toilet! Chemicals first and not last when you are done. When you put the chemicals in with a little water and let it sit for several weeks the chemical lost its potency and things got stinky. Chemicals need to be renewed in order to keep working.


    Ditto^^^^ clean well and leave empty if not being used
  • dave17352's avatar
    dave17352
    Explorer
    Apr 22, 2016
    Learjet wrote:
    leeper wrote:
    When I read your post I heard that you went camping, used the toilet with no chemicals in it, then drained the tanks, and then you added chemicals after you where done using it. No wonder it stunk! You first put in the chemicals with water, then use it, then you drain the tank of the chemicals and what ever you put in the toilet! Chemicals first and not last when you are done. When you put the chemicals in with a little water and let it sit for several weeks the chemical lost its potency and things got stinky. Chemicals need to be renewed in order to keep working.


    Ditto^^^^ clean well and leave empty if not being used


    A lot of people don't use chemicals at all. I charge my tanks up and can leave them for a month with no problems. I will be interested to see what he finds.
  • 1ofmany's avatar
    1ofmany
    Explorer
    Apr 22, 2016
    The roof vent for our black tank is right beside an air vent...sometimes I believe sewer odors are drawn inside because of this configuration. When we notice this (not often), we turn on the exhaust fan for that roof air vent. Seems to clear the smell.
  • djousma's avatar
    djousma
    Explorer
    Apr 22, 2016
    leeper wrote:
    When I read your post I heard that you went camping, used the toilet with no chemicals in it, then drained the tanks, and then you added chemicals after you where done using it. No wonder it stunk! You first put in the chemicals with water, then use it, then you drain the tank of the chemicals and what ever you put in the toilet! Chemicals first and not last when you are done. When you put the chemicals in with a little water and let it sit for several weeks the chemical lost its potency and things got stinky. Chemicals need to be renewed in order to keep working.


    I guess the way I read the OP is that he does what I do. After draining the tank, he "recharges" it with chemicals, and water so that it is ready to go for the next time. I don't think they said they used the tank without chems. I guess we wont know until he/she comes back for sure.

    If this is new trailer, then I'm going to go with the roof vent might be partially/fully plugged.

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