Gray tank mold odor

[WHThayer]

Do any of you have a mold odor coming up from your gray tank? I can only smell it when my nose is near the drain. How do you fix that??

[JRTJH]

I don't believe that you can "fix" sink odors. You have to "manage" them or "learn to live with" them....

First, the source of "sink odors" is food particles, grease and "bacterial action" in the gray tank. If you use your sink as a sink, you're going to introduce those components into the gray tank. Then, nature will take over and cause the odors you smell. You can't avoid that "IF" you use your sink.

So, the next option, since you're going to use the sink, is to "manage" the odors since few of us want to 'live with them"....

First, start by cleaning your gray tank as best you can. Start with a "good shot of DAWN and hot water. Mix about 2 cups of Dawn with as much hot water as you can pour down the drain. You can get about 7 or 8 gallons from your water heater and a couple of 5 gallon jugs from your house, making 15 or so gallons in the gray tank. Then "go for a tow" on a bumpy road to agitate the contents of the "goo" that's stuck to the tank walls. The more you can loosen, the more you'll eliminate the source of the smell. On the way home, while the contents are still warm, stop by a dump station and dump the tank. Follow with a thorough refill and dump again. That will rinse much of the remaining "goo" out of the tank.

Then, with "the cleanest tank you can easily achieve" use a "gray tank deororizer" as instructed on the bottle and ALWAYS dump your gray tank when storing the trailer..... Anytime that you park it for a couple of days with "stagnant water in the gray tank" it's going to "percolate and stink". So, never store with anything in the tanks.

I've found that the gray tank is actually more difficult to keep "odor free" than the black tank.... Most of us are "careful to use enough water in the black tank and to keep it flushed and relatively clean with our choice of deodorant when in use. We just don't do the same with the gray tank. First, there's no "flush valve" to wash it out, there's usually limited water through the tank (it seems to always be the last tank that gets full when camping) and there's seldom enough water in the tank to fully empty what's settled on the tank floor..... So, most gray tanks are "ready to stink" as soon as you close the dump valve and put it into storage for a few days in temperatures that are "ripe to grow stench"....

Get it clean, keep it clean and use deodorant if there's an objectionable odor.

[chuckster57]

Does your trailer have a separate galley tank or just one? Food particles can "rot" and give off a foul odor. Do you leave the gray tank valve open when hooked up to CG waste system?

[flybouy]

Originally Posted by WHThayer

Do any of you have a mold odor coming up from your gray tank? I can only smell it when my nose is near the drain. How do you fix that??

Good advice has been given on gray tank odors. But, I have questions. First, why is your nose by the drain? Secondly, mold smell? Are you sure that the smell is comming from the drain? Have you looked under the sink to see if a leak has resulted in mold?

[sourdough]

Originally Posted by flybouy

Good advice has been given on gray tank odors. But, I have questions. First, why is your nose by the drain? Secondly, mold smell? Are you sure that the smell is comming from the drain? Have you looked under the sink to see if a leak has resulted in mold?

Marshall brings up an excellent point. Leaking water left to sit can cause mold, rot wood etc. Many/most times it ends up smelling "musty". You might want to make certain you are smelling your gray tank and not "something else".

[LHaven]

Just got a promo from RV Upgrade Store, having a sale this week on Bio Kleen handing tank treatment, if you think that's worth a try. It's $31/gal, but at 2 ounces per 40 gallons in a gray tank (4 ounces for black), you'll get a lot of use out of it.

[Carl n Susan]

I bet you have an RV that is plumbed for a washer (up front in the general area of the bathroom) but you have not installed one. Attach a hose to each of the lines (stick the other end in the drain) and flush out the lines. Otherwise the stagnate water in there tends to cause odors in the sink. It is not a tank problem but the water you are running in the sink.

[travelin texans]

It could also be the anode rod in the water heater, if it's a Suburban brand heater, causing the hot water to smell.

[BDove]

Try using Unique. Just a little will naturally help your tank be odor free. I use in black and gray tanks. No odors. Very satisfied with this product. The cleaner and the treatment. Google it.

[flyingjack]

Travelin Texans; would you please expand on water heater anode smelling? We just got back with 53 days out and half way through noticed bad odor coming from master bath sink when hot water was turned on.

Thanks
Jack

[flybouy]

Originally Posted by flyingjack

Travelin Texans; would you please expand on water heater anode smelling? We just got back with 53 days out and half way through noticed bad odor coming from master bath sink when hot water was turned on.

Thanks
Jack

I know you asked Danny but I'll answer anyway. When the water heater anode begins to naturally desintigrate as it's designed to do the minerals from the water and the metal from the anode are going thru a chemical reaction. In hot weather, the water setting in the tank for an extended time will contain sulfer. That's what gives the water that "rotten egg" smell.

The cure is to remove the anode and flush with fresh water. If We're not going to use the camper in the summer for 2 or more weeks then I'll drain the tank. It only takes a few min. to drainm then fefill just prior to the next trip.

[travelin texans]

Originally Posted by flybouy

I know you asked Danny but I'll answer anyway. When the water heater anode begins to naturally desintigrate as it's designed to do the minerals from the water and the metal from the anode are going thru a chemical reaction. In hot weather, the water setting in the tank for an extended time will contain sulfer. That's what gives the water that "rotten egg" smell.

The cure is to remove the anode and flush with fresh water. If We're not going to use the camper in the summer for 2 or more weeks then I'll drain the tank. It only takes a few min. to drainm then fefill just prior to the next trip.

Yea! What he said!
If you have a Suburban brand water heater it will have an anode rod as it's a metal tank, the rod is sacrifical to corrode rather than the tank.
If you have an Atwood water heater its made differently & no anode rod required.
Be sure to shut off the water heater several hours before pulling the rod to cool the water down, shut off water supply, open hot faucets to relieve the pressure, use a 1 1/16" (if I recall correctly) to remove the rod, drain/rinse tank throughly, replace with new rod (about $10-12 at Walmart) using Teflon tape on the threads, refill tank.

[flyingjack]

Thanks guys for the quick response. Bought our Mountaineer new in 2013 and lived in RV while working western TX for first 6-7yrs. Had to replace anode sometimes every 3-4 months; sometimes every 8 months. Different water wells, different minerals. BUT, I didn't know about the smell issue; so thanks very much for that tip. I always keep a spare in 5er so I'll drain; maybe even run some vinegar through heater- redrain and install new anode. BTW; retired 3 yrs ago so 5er not getting the use it got when we more or less full-timed so water heater tank sits with water for longer periods of time. We drain fresh water tank when not in use but we seldom fill it as we're 90% using city fresh water at RV parks= very little boondocking.
Thanks again
Jack

[JRTJH]

Originally Posted by flyingjack

Thanks guys for the quick response. Bought our Mountaineer new in 2013 and lived in RV while working western TX for first 6-7yrs. Had to replace anode sometimes every 3-4 months; sometimes every 8 months. Different water wells, different minerals. BUT, I didn't know about the smell issue; so thanks very much for that tip. I always keep a spare in 5er so I'll drain; maybe even run some vinegar through heater- redrain and install new anode. BTW; retired 3 yrs ago so 5er not getting the use it got when we more or less full-timed so water heater tank sits with water for longer periods of time. We drain fresh water tank when not in use but we seldom fill it as we're 90% using city fresh water at RV parks= very little boondocking.
Thanks again
Jack

There's a procedure in the Suburban Owner's Manual that instructs on the "factory recommended way to eliminate the odors from stagnant water in the water heater:

ODOR FROM HOT WATER SYSTEM
Odor from the hot water system is not a service problem and many water supplies contain sufficient amounts of sulphur to produce an odor. The odor is similar to rotten eggs and is often referred to as "sulphur water". It is not harmful - only unpleasant to smell. Sulphur water can be caused by a chemical action or by bacteria. The solution to eliminate is chlorination of the water system . Add about six (6) ounces of chlorinated com m on household liquid bleach to each 10 gallons in the water tank. Then run the chlorinated water throughout the system, opening each faucet one at a time until you smell the chlorine. Let the RV sit for a few days and the chlorine should take care of the problem . Then you will need to take care of the chlorine. Remove the chlorine by flushing the system with fresh water. This m ay take several attempts. You may consider adding a filtering system that removes chlorine and prevents sulphur water. If the sulphur or rotten egg smell continues, flush the system once again as described above and replace anode rod as necessary.

I'm not sure that I'd use vinegar. In typical dilution ratios, it probably wouldn't be effecitve and at stronger strengths, it could affect the porcelain lining in the water heater.....

[flyingjack]

OK, chlorine it is. Will be done today.

Thanks again

Jack