Caravan Toilet Chemical Free Vent DIY cheap!

Here I have installed a caravan toilet ventilation system to my Thretford C260, which provides a comparable result as a commercially available kit from a German company (SOG). The Thretford C260 appears to have been designed to have an active venting system in mind as you will see in the video.
This makes this DIY project really quite simple and a very low cost addition to your van. This modification reduces or negates the need to add any chemicals to the cassette therefore lower cost to maintain, greater flexibility to dump as no chemicals makes it compatible with septic sewerage systems and reduces any odour in the van as the fan is always active while the toilet is in use.
The principal in use here can be adapted to other systems that have a passive vent pipe to the outside of the van (which most do as a necessity to vent any build up of gas in the cassette).
NOTE: I recently upgraded the fan to a Sunon 60mm fan to provide greater air throughput. The 50mm was OK just replacing the fan a a matter of course every couple of years and changed to the slightly bigger version.

[@nztwi]

Thanks for the video Tim. Great bit of diy!

[@michaelmatthews8490]

Tim I followed your instructions closely and have successfully completed installation. The system works well. I discovered that you can use short screws to secure the microswitch bracket and longer screws for the fan rather than using glue, this will make it easier to replace parts if necessary. I also extended the tuck in part at the back of the bracket to enable it to be secured to the wall. Great job Tim. Mick Matthews

[@timterry8714]

Great Mick, glad it was you experimented with screwing the switch bracket to the wall and not me as I was not sure if it was single or double skinned and didnt want screws appearing on the inside - would not be a good look. Its certainly a more secure way to retain the switch bracket. Thanks for the feedback and enhancements Mick.

[@andrewdarby8827]

Mick matthews Can we see a picture of your modification it would be really useful

[@famdrijver]

Though of heaps of ways of doing this also, I'm going to give method a go if I have room in that spot under the caravan. Thanks for your great video

[@timterry8714]

Hope its as successful as ours has been. Cheers Tim

[@famdrijver]

@@timterry8714 Sure was; I set up the microswitch to turn on as soon as you open the blade, making the switch placement easier. I also put the activated carbon on top of the 12-volt fan and used a flat aluminium vent under the caravan. My wife has never been happier.

[@gordonw7057]

Great work and thanks for sharing.

[@timterry8714]

Thank you! Cheers!

[@MurrayBridgeKid]

Thanks for sharing Tim.

[@timterry8714]

You are very welcome

[@robtaylor6966]

Good vid mate. Simple and easy, thanks for doing the homework and sharing this.

[@timterry8714]

No problem 👍

[@robtaylor6966]

Only comment id have is i think the 50mm fan (the one i have anyway) seems a bit too tame and the vacuum or sucking of the air is quite minimal. I’d like a bit more suction!

[@timterry8714]

No you dont need a huge amount of air movement, Rob. If you have a look at the SOG kits the fans are quite small. You just need some negative pressure as its only got to exchange the air in the cassette each time its used to assist the natural bacterial action and exhaust any unwanted odours outside and this small fan does that no problem. I have since installed a 60mm fan as my old secondhand 50mm fan ( test fan for proof of concept if you like) died and that was all I had to replace it with but the air movement is pretty much the same.

[@lawrencecurel7441]

WOW great video,I'm going to do that tommorow.ThanksTim.

[@timterry8714]

Good luck!

[@malvictory2521]

Great idea. I think the compartment is actually an overflow for if the cassette is full when the van is in motion. Care needs to be taken to eliminate the risk of overflow.

[@timterry8714]

well if thats the case the caravan manufacturer failed to create a exit point in the floor of the van. There is a "well" at the front of the floor which may be designed to catch overflow. I think it is simply a vent to release any build up of methane or whatever but it would be interesting to find out why it exists. Excellent for this purpose.

[@cmbubner]

Sorry mate, however you are incorrect, it is actually a vent, not an overflow.

[@jorjimaco5331]

Done it! Works a treat!!! 👍👍👏 so simple no switch tho, just on when you turn on caravan main 12v switch, next to nothing in current draw. Cheers 🍻

[@timterry8714]

Great Jorji, yes I suppose you could have it running continuously as it moves a very small amount of air and as you say a very small current draw. I guess it just shortens the life of the fan running all the time.

[@tomelder2230]

Thanks what a great bit work I love it

[@timterry8714]

Thanks Tom. We are away atm giving it the first try out and it works really well.

[@darrylnissen8247]

Hi Tim Just a comment about the size of the fan, the air flow is determined more by the size of the discharge hole in the floor because these computer fans are not designed for "head" more for displacement and when the discharge is reduced the affective area is that of the hole in the floor. That might explain why the SOG fan is the size that it is. Regards Darryl

[@timterry8714]

See above

[@darrylnissen8247]

Just watched the video again and saw you cut a 50 mm hole in the floor but then you put the two conduit connectors in your filter box which is your actual air flow restriction...interesting to see what adding conduit to the connectors does!

[@timterry8714]

Hi Darryl, we have been on the road for 6-7 weeks now and this has been brilliant. You need very little air movement to achieve the slightly negative pressure in the bowl to extract any unwanted odours and provide oxygen to the cassette to feed the bacteria breaking down the contents. Ours has worked flawlessly ) apart from the switch moving a bit and not activating - easily re-adjusted. Another person screwed the bracket in which is what I will do when I get home) and we have never added any chemicals.

[@jackmillin]

Nice idea, I've just been looking at the kit but at £120 I thought I can make one myself for next to nothing. I think I'll just wire it up to a permanent 12v that's on when the caravan is powered up.

[@timterry8714]

The fan cant suck air through the cassette when the toilet is shut so no real point in having it on permanently. But I guess why not otherwise. Cheers Tim

[@timterry8714]

Actually a friend wired it to permanent 12v (when van is powered up) and the fan died in about 3 or 4 months

[@AussieTracks]

Hi Tim Many thanks for the video. I installed it and all works well. I’d be grateful if you could clarify a couple of things. Firstly, did you upgrade the wiring on both the microswitch and the fan and secondly where did you buy your activated charcoal material please? Best wishes Peter

[@timterry8714]

Hi Peter, I havent changed the switch or wiring since installing it. I found the charcoal material on Ebay but cant see the listing anymore but this looks the same

[@timterry8714]

www.ebay.com.au/itm/164671699427?mkcid=16&mkevt=1&mkrid=705-154756-20017-0&ssspo=xieIH1mFSHi&sssrc=2349624&ssuid=mufvvukdq42&var=&widget_ver=artemis&media=COPY

[@AussieTracks]

Thanks Tim. I’ll search eBay and see how I go. When I find a good product I’ll let you know

[@christopherhenry282]

Thanks Tim for this video… as mentioned the cavity below the tank is an overflow and it can and will fill up if you’re not careful. I have a baby’s nappy stuffed in there because it is very hard to clean out. I would suggest a mesh bag of kitty litter or similar adjacent in the remaining space to reduce the risk of contaminating the fan etc. great job Mate!

[@jeffyoung922]

Hi where do you find the charcoal filter I have made a similar system to your one but the charcoal filter is harder to come by thanks

[@timterry8714]

www.ebay.com.au/itm/283888004628?mkcid=16&mkevt=1&mkrid=705-154756-20017-0&ssspo=lMCn-UUDQVW&sssrc=2349624&ssuid=mufvvukdq42&var=&widget_ver=artemis&media

[@janeanderson8236]

Not directly related to the venting system but can anyone tell me where the reed fuse/housing is located in this model C260, we cant find it anywhere.... help

[@timterry8714]

The fuse should be external to the toilet I would have thought at the fuse block in the caravan (trailer).

[@vicleague1229]

My toilet button doesnt work now. Anyideas???

[@timterry8714]

No. Blown fuse maybe