Grey Tank Odor

[offshore]

My DW says we have an odor in the bath room (I can't smell anything). It doesn't smell like the black tank, I am told, so that leaves the grey tank. I checked the vent pipe on the roof, its not obstructed. Has anyone flushed out their grey tank with bleach?

[NLOVNIT]

Check the AAV (air admittance valve) under the sink. There should be a pipe going up in the cabinet underneath with something looking like this: or this

It could be defective letting the gasses in.

Lori-

[RickO]

Actually, yes. I don't think the practice has a lot of fans but a grey tank can smell every bit as bad as a black one. I think the best thing to do would be to use an enzyme based product like Ridex... designed for septic systems... and give both tanks a good flushing and they refill with fresh water and the enzyme product.

The problem is that this takes several days to work and since we full time I haven't been able to use it effectively.

Just before traveling I have flushed and refilled my grey tank adding bleach (I forgot how much but you could search it here on the forum) and letting it slosh around in the tank all day. This seemed to be pretty effective. If you use bleach don't make the solution too strong and don't leave it in too long because it will tend to eat at the seals of your dump valves.

Good luck...

Rick

[RV Wizard]

One other thing to check if you have a washer or unit is prepped for a washer, that the "P" trap has water in it. If it is dry, it can let gases into the coach. This is true for all drains in the coach. One often overlooked possibility on some toilets is the over flow vent. Fill the toilet bowl to get some water into this overflow to again create a vapor seal. Good luck and keep us posted.

[Chickadee]

Have experienced same odor issue occasionally and have done the following:

Purchase a couple quart bottles (more if needed) of Liquid Plumber (Industrial) GEL type. No, we've NOT experienced any decernable seal OR drain pipe damage over 5 yrs of use.

Ran hot water into a.) kitchen sink drain, b.) bathroom sink drain, and c.) shower drain. Just enough to momentarily flush drain pipes to be teated.

Pour 1/2 + bottle (so all drains get a good dose and all Liquid Plummer is used up) into each drain (Kitchen, Bathroom sink, Shower) and let it stand WITHOUT running ANY water into treated drains for at least about 1/2 hour (Directions say 15 mins. but we feel longer is better).

After open drains and drain lines have soaked in Liquid Plumber for selected period of time, CLOSE/SEAL drain stoppers in bath sinks and close kitchen sink with sealed drain basket. Then fill kitchen sink and bathroom sink(s) with HOT water to the brim. Once each sink is full, and,.... STARTING at the sink drain you think is furthest up line (ie., furthest from the grey tank) quickly open furthest up line drain FIRST, so the weight and volume of hot water in that sink flushes down drain line. Then open drain on next closest sink, etc. etc.

To assure a good drain system flush, we refill all sinks and repeat a second time.

Since most of us can't plug a shower drain, ya can pour a bucket of hot water down the shower drain then maybe take shower following clean up.

OH!....don't know if it helps, but we also ALWAYS flush out the grey water tank at least once following all of above.

Give er a try.....think you'll like the results!! Odor GONE...till next time ya detect drain line build up odor....for us, usually about 4 to 5 months between treatments.

Steve

[offshore]

OK, now I have a lot of options to try, I'll keep you'll up dated as I continue with my journey. Thanks for the suggestions.

[Batman_777]

Are you guys talking about the air-vents under each sink, etc? They have a rubber waffer that opens up as water rushes down the drain. This stops a vacuum from building up behind the water flow. The air vent is required for each drain that does not have an external pipe running out of the roof.

Check Vent: You can see if they are bad by removing it and holding a flashlight up to it. There should not be any light getting through. You can try cleaning it. Sometimes that works, sometimes it does not.

There are various grades or quality check-vents. Some are very cheap and do not last.

The problem is when they do not close and the rubber flat doesn't seat.

They are easily removed by unscrewing (by hand). Tighten gently.. There's no need to over tighten. If they do not seat properly, foul sewage gasses from your waste tanks will emit from them.
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[Batman_777]

Fleetwood told me (over the phone) they sanitize waste tanks with bleach. When RV's come in the plant for service if there is anything to do with the tanks, they flush and sanitize the tanks immediately with bleach.

I have since tried it several times by dumping a 3 quart jug into the grey (ro gallon tank) and 3 quarts into the black tank (50 gallon tank). Let it stand for a few hours and then flush it out before any seal damage can occur. It has done wonders for odor control and I'm sure there is a lot less bacteria in there.

Someone mentioned, putting in some bleach with half to 3/4 tanks full and drive a bit to swish the stuff around before dumping.

[JDooley]

I use lemon joy dishwashing soap which leaves no smell. For the last ten years no problem

[offshore]

Thanks to all of you that have contributed in some form or another. Every little bit of information goes a long way. (by the way this is Mrs. Offshore speaking). I am the one who is smelling this odor. My husband has no sense of smell so, this is like speaking to a brick wall, bless his heart. The smell is like an old wet diaper. You can even smell it in one of the basement doors that we keep locked which is located opposite the bathroom side. I do believe it is more than just the grey tank. Any other input with my lastest information will be great. We will definetly give it a try on cleaning out both tanks though. Thank you so much. You guys are such a great help.

[NLOVNIT]

The "smells" are an elusive bugger. Eventually you find its source, but it can be frustrating & take a lot of trial & error. Hang in there, we'll keep offering up things to check.

Lori-

[RV Wizard]

If you are smelling odors in a compartment below the floor line then you could have a drain line to tank issue. This is going to be harder to find and repair. Over fill the grey tank until water backs up into shower or tub. Let it stand for as much as an hour but keep a look out for a leak around the grey tank. This is probably over the rear axle but might leak into a compartment. If the tank leaks then you will need to access the joint and redo it to solve the problem.

[Batman_777]

Above Post: The smell is like an old wet diaper..... Mildew?

[Chickadee]

Clean and flush the drains, traps, and drain lines occasionally as mentioned above....you'll be amazed at the improvement.

Steve