Sewer odor

[GRedman]

I have a 2015 Seneca and we are always getting a strong sewer odor in the bathroom. I've flushed the tank after each use yet it still smells. We also add chemical after each trip. Also, I don't open the black valve until it's time to leave when on short trips. Has any other Seneca owners experienced this?

Thanks,

[plasma800]

lot of times it's the grey tank that smells.

Your unit probably has a back flow preventer under the sink, and those are notorious for letting smells out... or it could be the shower drain, if it's not got water in it, smell can come back up.

I recommend you use Happy Campers powder for both grey and black.

[gregoryd73]

My Son got that too and found that the P-trap on the shower had tried out due to non-use in his camper. Make sure all your sinks and the shower have water put down them from time-to-time if not using them. Also, you might check the vent to the roof to make sure that is open and that wasps haven't built a nest and plugged it. Hope this helps.

[TonyDi]

You can try flushing the tanks. A little Dawn in the grey tank will help cut grease deposits and clean it well.
I also use Happy Camper in my black tank and it works great. They also make an Extreme Cleaner for hard to treat tanks.

[lanerd]

You know, the gray tank can smell just as bad. The first thing I would do is replace the Air Admittance Valve (AAV) that is located under the bathroom sink. You can find a replacement at Home Depot or Lowes.

If it is indeed an odor coming from the black tank, I would first close the roof vent and see if that helps. If not, sounds like you may have a leaky toilet seal.

Sometimes just "flushing" the tank may not be sufficient enough to remove all the "stuff" and tp that can cling to the walls of the tank. What we do is prior to a travel day, we add a cup full of liquid laundry detergent (we use Oxy Clean) to the black and gray tank along with about 5 gallons of water. We also will add a cap full of Calgon water softener to each. The soapy solution will slosh around during traveling and will soften hard deposits and also remove anything stuck to walls of the tank and tank sensors. The Calgon will make the tank's interior slippery thus reducing the possibility of stuff sticking to it.

Try this the next time you travel and see if it helps with your odors. I've also heard positive results from Happy Camper tank additive.

Good luck and I hope this helps

Ron