Stinky kitchen sink

[Possum51]

We don't know why the kitchen sink drains smell so bad! I have been using Thetford Gray Water Odor Control but it hasn't helped. When we leave the coach and come back in it really hits you in the face! It smells like musty water! We have been traveling in the trailer for 3 months and this problem has only been happening for the last 2 weeks but it's getting worse! We do have a little amount of water in our fresh water tank which we have never had before. Could it be the fresh water tank? We put that water in when we first started traveling 3 months ago. Is there a chemical we should have put in there? Thanks

 

[danemayer]

Hi Pat,

There's probably a one-way air admittance valve under the sink. If it's become two-way, it allows odors from the tank into the kitchen. Locate yours and put a baggy over it temporarily to see if that's where the odor originates. If so, you can probably find one at Home Depot or Lowes for around $10.

 

[buddyboy]

If you've got water 3 months old in your fresh water tank, you should dump it and sanitize the tank. Probably bacteria or algae bloom in the tank. On our boat, we'd put new water in about 1/2 tank, add bleach and finish filling with water. We'd let it sit a few hours and then dump it.

 

[JohnD]

If you've got water 3 months old in your fresh water tank, you should dump it and sanitize the tank. Probably bacteria or algae bloom in the tank. On our boat, we'd put new water in about 1/2 tank, add bleach and finish filling with water. We'd let it sit a few hours and then dump it.

How much bleach?

 

[buddyboy]

Depending on how skanky it smelled, 1/2 - 1 cup for every 10 gallons. After we dumped it, we'd fill with fresh water and dump that before using it.

 

[Garypowell]

Dan is probably correct in his diagnosis. Another way to solve the problem is to simply remove the air valve and plug the line. After 2 rounds of replacing the air add valve I plugged the line in both kitchen and bath. Problem solved.

Some cautioned me that when draining tanks we could lose the water in the P traps but this has not happen in over a year with about 8 months of travel.

 

[Possum51]

Dan I replaced it this morning. Cheap enough fix! Only cost $5.65 at Hone Depot! RV tech was going to charge me $186.00!! Thanks for your expertise!!

 

[farside291]

We keep plastic zip lock bags with a string tied around the pipe on all of ours. No more smells! I think when we travel the water in the traps flows back to the tanks which allows the smell from the grey tank to come up through the drain. Sometimes when we stop after driving we notice the smell in the RV. Run water back in the trap and open the ceiling vent for awhile and the smell goes away.

 

[jmgratz]

If you leave the gray tanks drain valve open you could have some odor backflow into the coach. Only open the gray valves when draining the tank and only drain the tank when full. By leaving them open all the time debris can build up in the tank such as food particles which don't flow out. When draining the tank don't forget to flush them as well.

 

[cookie]

I think when we travel the water in the traps flows back to the tanks which allows the smell from the grey tank to come up through the drain. Sometimes when we stop after driving we notice the smell in the RV. Run water back in the trap and open the ceiling vent for awhile and the smell goes away.

I have to agree. A couple of weeks ago we had an odor in the front closet when running the Fantastic fan. I suspected that the water in the P-trap for the washer must have splashed out.
We did a load of laundry and the odor went away.

Peace
Dave

 

[StrongJava]

Thank you OP and danemayer! I suspect this is my problem too, and now due to this great forum, I have an idea how to fix it.