Community Forums

redragon1293 · 05-06-2021, 09:52 AM

Hi,

I am hoping that some of you have run into this issue and can suggest a couple of things to look at...
We have a new 250RDS and are experiencing some strong septic odors in the coach when we flush the toilet after the tanks gets 1/3 full. We are full timers and have been in the coach for about a 4 to 6 weeks now. We have dumped, flushed, and filled twice, and use the same black tank pods (2) that we used in the DP. We did not have the issue in the DP so I am assuming the pods are working..?
We have tried with the vent open (fan off) and with vent closed.. no change.

Any thoughts?
Thanks
Jim

litzdog911 · 05-06-2021, 09:54 AM

We've had no issues with our black tank smell in our 280KVS. We use Happy Camper treatment. Be sure that your roof vent isn't clogged. Sometimes birds or debris can clog that.

redragon1293 · 05-06-2021, 10:13 AM

Thanks litzdog911.
I had 360 vents on the DP and really liked them. I was thinking about putting a pair on the 250 once we get to Flagstaff..

Jim

Cumminsfan · 05-06-2021, 01:25 PM

I have pretty much the same TT in a 2019 25RDS. Never had sewer odors and we rarely use chemicals. I'm assuming that the toilet holds a little water in the bowl after flushing?
The one thing that keeps the stink down is not using the vent in the bathroom ceiling at the same time. We've left a 1/2 full tank of sewage in it for a couple weeks at a time. As long as the bowl has some water in it to cover the ball gasket you shouldn't have stink.
I think I would look at the base gasket too. Maybe it's not sealed well?

Old-Biscuit · 05-06-2021, 01:55 PM

Black tank stink WHEN Flushing and tank 1/3 level
Minor smell from black tank is normal when flushing as toilet is wide open to black tank
But if toilet 'burps' back at you when flushing......venting issue

Need to check the black tank vent line
If it has slipped down into tank the level can block the vent line and when you flush the 'air' in tank MUST leave so it comes back up thru toilet line vs going up/out vent line

Go up on roof and remove black tank vent cap
The end of the vent line should be level/close to roof line
IF it is Down below roof line then pull it back up (vise grips) then secure it with a wood screw thru side of pipe into roof sheathing

If it has NOT slipped down then you need to run garden hose down vent line and blast away ---clearing vent line

pdxgwj · 05-07-2021, 06:18 AM

Are you sure it’s the black tank? The grey tank can smell pretty fowl and it will come up thru the drains. The only time you would smell the black tank inside is when you flush,unless the vent was not connected. I put deodorizer in both.

redragon1293 · 05-07-2021, 08:34 AM

Guys,
Thanks for the great feedback...
I have done some additional sniffing out for the source of the problem

It seems like the odor is strongest in the hallway opposite of the bathroom where the vent stack is. I have ordered a pair of the 360 vents and will pull the existing caps off when we get to Flagstaff late next week and check to make sure they are flush with the roof. (Old-Biscuit)

Cumminsfan: the ball seal is holding water, I have tried with vent closed and open the intensity seems to be the same, at least to me. The toilet seems well anchored, I have not seen any seepage and when I get down on the floor I am not smelling anything after the ball is closed. Not sure how to check the seal without pulling up the toilet.

pdxgwj: I am pretty sure that it is a septic smell, to me there is a difference between the 2 tanks. We found in the Dutch Star that it worked out best if we did not put any kitchen sink waste into the tank and do not allow any grease to go down the drain and we use Happy Camper from day one. Besides the rig is brand new... only filled the tanks twice so far.

Old-Biscuit: We are not getting any burping. I also noticed that the smell seems to be strongest near the wall where the vent stack is run. One curious note (may not mean a thing but..) it takes about 15 seconds after a flush for the smell to become noticeable in the hallway and before we can smell it in the bathroom/rest of the rig.

It is much appreciated having a group to use as a sounding board and solution ideas...

Thanks much..

Jim

redragon1293 · 05-07-2021, 08:50 AM

Guys,

One thing I forgot to mention in the original post...
It seems to take about a week after dumping/flushing for the smells to appear.
If the vent pipe has fallen down into the tank then this might explain it?
I will post what I find next week when I install the 360's..

Thanks again

Old-Biscuit · 05-07-2021, 07:03 PM

Sounds like vent pipe inside the wall is cracked or coupler not glued

Should be NO smell in wall area
Smell would only be up thru toilet WHEN flushing...not after wards/time delayed

redragon1293 · 05-27-2021, 10:39 AM

Update:
I replaced the factory vents with 360 vents. It has been almost a week and the black is at 2/3 full..... No more odors.
Thanks all for the great feedback.

Jim

Diamond Joe · 05-30-2021, 06:16 PM

Red dragon, keep us posted how this fix works after a few tanks full. I've been having the same issue with tank odor for the first time after 5 years, 20k miles, and over 250 nights in my arctic fox 25r.

My most recent trip, for 7 weeks was the first trip with my new solar system; 800 watts of panels on roof. One of the panels sits just above the roof vents for the tanks. I'm guessing that the ventilation is insufficient now. Gonna try some 360 vents, those look good. I've been successfully dealing with it however, by just adding another scoop of Odorlos™️ when the smells waft up.

Btw, I've tried pods, and liquids and have found Odorlos crystals to be the superior product. I have to order it online now as CW and Walmart stopped carrying it.

redragon1293 · 05-31-2021, 06:21 AM

Whangler,
I have 1480W on the roof and the panels come to within 6 inches on both sides of the vents. I am wondering if I caused my own problem getting too close to the old vents. I put the system in as soon as we got the rig so I cannot do a before and after comparison. The 360 seems to work with less air movement. I will do another update after a few more tanks.
I need to check out the Odorlos product..thanks for the tip

keymastr · 06-07-2021, 11:31 AM

I think you are correct that the placement of the panels has caused the airflow to come down the vent pipe rather than up and out. I lived next door to a house that was sold and a high rise condo was built in it's place and the wind would come over the condo roof and down my chimney so after it was built I could not burn the fireplace without the house filling with smoke. I bought a fancy chimney cap that rotated similar to the vent cap you reference and it helped some but did not completely fix the issue. Hopefully you have better luck.

On a side note, if your system is working properly there is no need for tank treatments and nothing you put in there will make it's contents smell the least bit acceptable. We have been full time for nearly 18 months and use nothing but water and have never smelled a thing from any of our tanks. Tank treatments also contain chemicals that are harmful to sceptic tank bacteria and slow or kill the beneficial bacteria they rely on to break down the waste so do not use them if you dump into a sceptic system. They really are just a waste of money, literally just throwing it down the toilet.