Community Forums

Jim Stewart · 02-17-2010, 10:07 AM

We have had an on again off again sewer smell in the inside of our MH. After awhile, we narrowed it down to when we dumped the black tank or ran the cloths washer. When we dumped the black tank it was all over the MH, when we did laundry it was emanating from the rear with a smell cloud wafting forward.

We have a Splendide Combo washer/dryer, so I started looking. It has a in-line stack pipe with an anti-siphon valve on the top of the 1-1/2 inch pipe. I took it off and the valve had a little rubber flap on it that is supposed to go up and down when expelled waste drains below it and to keep from sucking the fluid out of the trap when dumping the black tank. It seemed like a cheap valve, yet seemed to be working as designed, NOT!

I went to Home Depot and found the valve below, it is an Oatey #39012. It is a much better quality valve and has a spring above the flap to force it down after it is pushed open. It screwed right in the stack pipe and now, no smell during laundry and I dumped the black tank, again, no odor whatsoever. Cost $5.29, cheapest fix yet for the MH. Now we can do laundry while entertaining guests without them thinking one of us messed our pants!

Route 66 · 02-17-2010, 10:18 AM

Those anti-siphon valves are a common problem.

RV Wizard · 02-18-2010, 02:56 AM

Jim, glad you found the problem. you might also want to; if you haven't already, reply to the original post of the odor problem. Thanks for keeping us posted.

wa8yxm · 02-18-2010, 09:39 AM

Interesting that you had smell from THAT vavle when dumping the black tank.. Or does the Splendie dump into the black (Should go gray if I'm not mistaken)

Jim Stewart · 02-18-2010, 11:23 AM

Well, while parked, prior to dumping the black, I close the grey valve and let some water fill the grey tank. Then I dump the black, after it dumps, I open the grey to rinse the black hose and fittings. When completed I close the black and leave the grey open. The water is often sucked out of the trap for the washer by the dumping of the grey. With the grey valve open the smell from the sewer, not the black tank, comes back into the MH. If the valve is not working, the trap may empty and then the smell can waft up.

adj · 02-18-2010, 04:38 PM

My washer drains directly into a stand pipe with a "J" trap. There is no anti-siphon valve.

Lindsay Richards · 02-18-2010, 06:06 PM

The gray water tank can have a horrible smell also. We had the same problem and traced it back to the same valve on gray system under the vanity sink. The spring gives out. Get one of those roof vent caps that points into the wind also.

az bound · 02-20-2010, 05:54 AM

We are having a similar problem in bathroom. When we turn on the exhaust fan with the door closed it draws in odor in just a few seconds. With the door open it doesn't happen. Tried capping off the anti-siphon valve, made sure the p-traps were full wc valve closed and some water in it. turn on the exhaust fan and same problem occurs. Cant find where it is drawing the sewer odor from. Help!!!! stinky in here.

exrench · 02-20-2010, 06:46 PM

If you have a washer/dryer in the bathroom,it may need to be "short cycled to fill it's dedicated "P" trap,as they often are sucked dry when the gray water tank is dumped.

Snowman 1 · 02-20-2010, 07:40 PM

Another name for the valve pictured is a Studor valve. They're designed to allow air in but not let gases escape. They eliminate a roof vent. They have very specific limitations in how they are installed, any liquid that comes in contact with them ruins the valve.

gg · 02-25-2010, 02:41 PM

Found same valve letting stink in behind the Washer cabinet when dumping.

I have not added the W/D combo yet because DW has not ask for it and I let sleeping dogs lie.

I first though the dealer applied pink anti freeze in the P trap. as this was the first thing in view by the stink source. Wrong as I applied the pink into the P trap it promply ran out. Removed the fitting and cleaned the sawdust out of the threads and reinstalled. Added Pink

Next Dump - a slight stink again in the Wash cabinet??

unloaded the cabinet and found Stink at The Valve and found that their was odor from the ptrap also. I deduced that the dumping pull the Pink out so the valve was not working.

I decided to Duck Tape both the Valve and the Openning to the Washer dump hose shut.

1 year later NO Stink

- If a washer is installed then I'll buy a better Valve.

Lorna · 02-25-2010, 06:24 PM

Quote:

Originally Posted by Snowman 1

Another name for the valve pictured is a Studor valve.

I've always been told that they were called Cheater valves (air admittance valves). I believe that Studor is a manufacturer.

From Jokes, Cartoons, Food, Health, Sweepstakes, Word Power | Reader's Digest Magazine Articles

AAV Vent (alternative method)
An air admittance valve, approved for use in certain states, provides air for drainage but remains shut to sewer gases. And it eliminates the need to run a vent pipe under the floor.
If installed correctly, they can work in most single-family homes, as long as there’s one primary main vent that penetrates the roof to outside air. Drawbacks? Sometimes AAVs can’t keep up with the venting needs of high-volume (18 to 22 gpm) discharge washers and dishwashers. And AAVs have a tougher time relieving pressure in the drainage and vent system of five-story buildings and higher.
For more information on AAVs, contact the following manufacturers:
Ayrlett: (877) 338-7455, www.ayrlett.com
Magic Vent: (800) 231-3345, www.rectorseal.com
Oatey: (800) 321-9532, www.oatey.com
Studor: (800)447-4721, www.studor.com

bldrbob · 02-25-2010, 07:12 PM

az bound
We had a similar problem. We have a Sealand toilet which is 2 piece. The toilet was not holding water when we bought it so the dealer changed the seals.To make the story short he didn't tighten the clamp enough. When you sat on the toilet it would leak under the outer cover and collect on top of the tank.The fan would draw the odor up thru the small openings in the floor when the door was closed.Removing the panel near the tank revealed the puddle on top of the tank.
If dumping the grey tank is draining the traps you should check the vent for blockage.
BOB

J Walker · 02-26-2010, 10:19 AM

Quote:

Originally Posted by Jim Stewart

Well, while parked, prior to dumping the black, I close the grey valve and let some water fill the grey tank. Then I dump the black, after it dumps, I open the grey to rinse the black hose and fittings. When completed I close the black and leave the grey open. The water is often sucked out of the trap for the washer by the dumping of the grey. With the grey valve open the smell from the sewer, not the black tank, comes back into the MH. If the valve is not working, the trap may empty and then the smell can waft up.

That should not happen. The vent on your gray tank should take care of the vacuum created when dumping the gray tank. You could check to see if your vent pipe is too long and extends into the gray tank too far putting it underwater although it is unlikely. You could dump the gray water by opening the valve less than 100%. I have never lost the water in traps when dumping.