Old stinky toilet problem new idea

Nice one Earl!

I am going to do the fan mod I outlined above but it will be exiting the TM wall near the existing grey tank vent. I will probably use a variant of your riser but because I'm exiting further forward it will be attached to the back of the front shell at the roof line.

Peter

[ELM-JLM]

Hi peter,
I think the fan is an even better idea in that you can control the exhaust! Camping world also had a Solar Vent Cap with a small fan built in. I opted for the Cyclone Vent in hopes that it will do the job without power! I'll let you all know very soon if it fulfills my expectations!

[ELM-JLM]

Originally Posted by kokilo

Nice one Earl!

I am going to do the fan mod I outlined above but it will be exiting the TM wall near the existing grey tank vent. I will probably use a variant of your riser but because I'm exiting further forward it will be attached to the back of the front shell at the roof line.

Peter

I'm not sure what or where the gray water vent is but if you can T into the pipe, then the fan would exhaust both simultaneously and exit from the same vent. Then a snorkle type cover could be used to direct it to the sky!

[mjlaupp]

Originally Posted by ELM-JLM

I'm not sure what or where the gray water vent is.....

It's through the wall under the bath sink.

.....but if you can T into the pipe, then the fan would exhaust both simultaneously and exit from the same vent......

Not a good idea. I have had soap suds come out of the grey tank vent on several occasions after draining the kitchen sink. Don't think the fan motor would like that!

I thought about hooking the grey water vent and the thetford vent both into the fan and exhausting them both together but there are a few problems.
- The vent for the grey water tank comes out under the kitchen sink so its hard to work on unless I remove the sink.
- Any air leaks in the grey water system (dry traps) may defeat the suction needed to keep the thetford smell in the vent line.

The gmc motorhome version does tie in both the grey and black water vents but he had to put in an extra trap because of some problem with smell being broadcast through the grey water system when underway.

I think I will keep it simple and do just the thetford vent first. If this works then the rest can be added later.

Thanks, Peter

[ELM-JLM]

Originally Posted by mjlaupp

It's through the wall under the bath sink.

Not a good idea. I have had soap suds come out of the grey tank vent on several occasions after draining the kitchen sink. Don't think the fan motor would like that!

Thanks for that info! I use a brass radiator drain valve in my gray water line and allow it to drip. I always have enough left to flush when dumping!

[ELM-JLM]

Originally Posted by kokilo

I thought about hooking the grey water vent and the thetford vent both into the fan and exhausting them both together but there are a few problems.
- The vent for the grey water tank comes out under the kitchen sink so its hard to work on unless I remove the sink.
- Any air leaks in the grey water system (dry traps) may defeat the suction needed to keep the thetford smell in the vent line.

The gmc motorhome version does tie in both the grey and black water vents but he had to put in an extra trap because of some problem with smell being broadcast through the grey water system when underway.

I think I will keep it simple and do just the thetford vent first. If this works then the rest can be added later.

Thanks, Peter

Research is invaluable! Thanks for the heads up!

Hi,

We have installed an exhaust fan which runs continuously to isolate the smell of the thetford toilet from the air inside the trailer. Cost is around 75.00 for parts and a few days of time to install the system.

The air is exhausted from the toilet via the right hand vent hole in toilet top(requires moving gauge to left hand hole).

The exhaust pipe is 1 1/2" ID ABS and all holes in walls are 2" in diameter.

Materials: (approx $75.00)
1 - Lil Stanker exhaust fan kit 1 1/2 inch size.
3 - 1 1/2 abs 45 degree F/F connector
1 - 1 1/2 abs 90 degree F/F connector
24" - 1 1/2" ID abs pipe
1 - Battery box vent cover.
ABS solvent/glue, Silicon Grease, Silicon seal, insulating foam, electrical connectors.

Moving the Thetford gauge from right to left hole in top:
The only way to move the gauge is to remove the top of the toilet, work the gauge out of its hole (its like a big rubber stopper) and put it in the other vent/gauge hole. Be sure to remove flapper valve on end of chute into toilet. See Shrimpburrito's vinyl flap replacement. Replace toilet top with top seal in place and silicon seal on front screws

Order of connections:
Thetford toilet right hand vent hole. Mates with 1 1/2" ID ABS pipe. Slip fit.
1 7/8" of 1 1/2 pipe
45 degree union f/f 1 1/2" Allows movement in two planes. Widens pipe to wall distance to allow Lil Stanker fan space in the cabinet and also bridges and elevates from toilet. Glued both ends.
3" of 1 1/2 pipe
45 degree union f/f 1 1/2" Allows pipe to go through cabinet side at 90 degrees. Glued end closest toilet.
3" of 1 1/2 pipe
Fan inlet Slip fit.
Fan outlet Slip fit.
1 7/8" of 1 1/2 pipe
45 degree union f/f 1 1/2" Drops exit to a convenient area to work in (once trap pulled from sink) Glued both ends.
3 1/8" of 1 1/2 pipe
90 degree union f/f 1 1/2" Orients the exit at 90 degrees to wall. Glued end furthest from wall.
?.. this one should be measured at the wall drill point and depends on flange selection" 1 1/2 pipe
Trailer wall.

The fan is a tight fit between the hole through the side of the sink cabinet and the outside wall of trailer. It is installed right behind the cabinet wall on the 1 1/2 pipe going through the cabinet wall. The hole in the cabinet was done at the right height for the plumbing parts but far enough from the wall so the stanker will fit under the cabinet between the pipe hole and the trailer wall.

Exhaust is routed to a convenient point to cut through the trailer wall. Temporarily removing the trap from the sink helped to make things more accessible.

I installed the switch and box beside the fan switch on the sink cabinet . Power is taken by tapping into the +12v and ground going to the Thetford pump motor. A white wire and a black wire in the cabinet. . There are two 3M 10 - 12 gauge scotchlok splices That can be used by adding the green and white from the fan.

The assembly is glued on all connections except those needed for adjustment/dis-assembly/repair.
So there are slip fits at the thetford, slip fits into the fan assembly input and output sides and a slip fit between the last 90 degree connector and the trailer wall. Slip fits can be lubricated with silicon grease or petroleum jelly if they are downstream of the fan (fan exhaust, 90 degree female on wall side. The silicon grease is harder to pull apart while the petroleum jelly is more of a mess. Use is optional for the slip fits upstream of the fan because they are under negative air pressure.

So far the noise of the fan is well within our tolerance levels. The amount of noise does depend on mounting the fan so it doesn't vibrate against a wall or piece of plywood. Supported by my hands with no input or output load it is as quiet as advertised. However, once subject to the loads of the system and the resonance of the fan against the cabinet or trailer wall it is louder. I could probably get it a bit quieter but I don't feel its worth the trouble right now. So it must be quiet enough.

Would like:
I am still experimenting with fan locations and use of hose versus pipe.
I would like a heavier flange on the TM sidewall where the vent exits. Perhaps mount the fan directly on the Heavier flange. Perhaps hang the fan and use hose to isolate vibration.
I would like an alternate vent routing for storage mode so it can vent the toilet through the floor and it will smell fresh when opened.

The fan has been running on low for a week now and the Thetford toilet smell is gone from the airspace in the trailer. No odor...gone.

It works great. It removes all smells and leaves just a whisper of noise in its place.


Peter

I have had some success by adding the Potty-Toddy tablets.

One for normal days.

Two for hot days.

As long as the outside temperature is less than 90, no one complains.

For hot days I also will sometimes (if I think of it) pour only half a bottle of the blue stuff in. Then when the gauge shows almost half full I add the rest. Not sure if it helps, but it just seems reasonable.

[Lesherp]

Peter this is my next project. I got the Lil Stanker the other day in the mail and have put the battery box vent on my list of things I am ordering from TM. Thanks for the pictures they have been invaluable to me on this sight. I can’t tell exactly how you connected the pipe to the toilet. From what I have been reading it should be done in a way that will allow you to pull the toilet if needed so it must be removable but obviously air tight. Earl how did you plug into the toilet? Peter where did you connect the wiring to the power? Please post if any of your experimentation results in any additional ways to make this better. I hope to get this done before too long.