Holding tank odor

[troutman1971]

I have had the wonderful black tank odor in my coach while traveling down the road with a partially filled tank and having someone use the toilet. Is my holding tank vent working properly? Would a replacement vent cap be of any help?

Thanks

[Roger H]

Mark, what are you using for deodorant chemicals, and how often? Technically, the john isn't supposed to be used while the coach is in motion.

[troutman1971]

I've been using the Walex bio pack. Use after emptying the tank and when the tank is 1/2 full. Yeah it's tough to not let the kids use the toilet when nature calls and we are crusing down the road.

[Mike Astley]

When traveling, there air pressures within the RV can be different especially if driving with windows down, potentially pulling air up from the tank. Best you can do is make sure toilet is flushed with bathroom door closed.

Also, do not flush when you have the fantastic fan on blowing air out of the RV as this will bring up lots of odors from the black tank! (voice of experience)

[stevek]

I try to always keep an inch of water over the top of the Toilet Flapper Valve, to make sure everything is sealed real good. And keep chemicals in the tank that I buy from Walmart.

[rhyde]

Our Fantastic Fan is under a Camco vent cover so when parked at a campsite we leave the FF cover open all the time, rain or shine. If we forget to close it when we hit the road, it will create a low pressure in the coach which is enough to defeat the lavatory drain trap (which in the 24RB drains to the black tank) and pull fumes into the coach. Once we pull over and close the FF cover, the smell clears right up.

[oliverpsmile]

Mark

If you have Bravura toilet the the smell, most likely comes form a broken seal of the flush mechanism.
Mine seal is fully deteriorated (same symptoms - When the exhaust fan is on, the smell is unbearable). A replacement seal/gasket is readily available on the market. However, I decided to change the toilet (~$175) with some additional footing for higher seating. My local plumber will do the job.

PS Last time I was filling the holding tank for cleaning (I over did it), a smelly water came out trough the seal. Upon checking the leak I discovered the horrible condition of the original seal/gasket.

[karls]

As mentioned, the two paths for black tank fumes to get in the coach are through the toilet or sink (24RB). The toilet seal must hold water after flushing or it is leaking. And the sink trap must also hold water, although that's tougher to see. As a get-me-home solution to the leaking toilet flush plate I stuffed a plastic shopping bag filled with a big wet rag in the toilet. That worked.

To solve the problem in our 1998 24RB I installed a new commode ( the foot valve was dripping too), and a venturi roof vent. No more odor.

[Bonnie McDowell]

Mine does not hold water after flushing. Is it hard to replace the seal? And where do I get it?

[bfadmin]

Bonnie,

Most qualified RV repair shops will have the parts to replace you leaking toiler seal.

[stevek]

Also search YouTube and videos for do it your self of installing the gasket.
Doesn't look like that hard of job.
But it does look like you have to completely remove the whole toilet.