I as reading about this type of system, and the newspaper article I read showed picture showed the toilet exhaust vent underneath the van pointing outwards from the side . Below is a general link to the product.
The below comment is from someone who converted their existing system with a DIY kit;
"Having done this mod I decided to give a full test without chemical for a few weeks, and yes you can do without it and there will be no smell indoors BUT be aware that the addition of air to a cassette of sewerage WILL NOT treat it and wont make it smell any better when you empty it. Also to really use this system you need to be camped out on your own as there is a fair aroma when the slide is open and someone is using the throne. Also if you are unlucky that aroma will re-enter your home via a downwind window. Yuck! It would NEVER be an option for me in a caravan park if you want the neighbours to speak with you again. My advice, in the bush sure use the system but in the real world get yourself some Aquachem Premium Blue and turn it off. Note, when travelling replace the vented cap with the standard unless you want a mess to clean up! "
I would hate to be in a caravan park bay alongside someone who had one of these, especially if it was pointed in the direction of my annex or open door, and I have read on this forum where some people do not like using the park toilets and use their inbuilt job, hopefully not with one of these.
-- Edited by Duh on Saturday 2nd of November 2013 07:50:07 PM
"This draws air down into the toilet bowl - preventing any smell at all from rising - and into the holding tank and it is then exhausted through the hose and ventilation fan into a small exterior housing which contains a carbon filter (which should be replaced once a year) which removes odours before the air escapes to the outside."
Has anyone got or used one of these systems and how did they find the exhaust system to the outside?
-- Edited by Duh on Saturday 2nd of November 2013 09:14:09 PM
I have fitted my own made up SOG unit copied from another forum members write up and yes it does work good especially when opening the Blade Valve there is no unwanted smells rising into the van interior. We also only use the cheap Napisan product with great results. When in a van park or close by tend to not have SOG exhaust fan on 24/7 only when using toilet. Only when tank is close to full is there excessive amounts of fumes noticed if the wind is blowing from that side of van which can be noticed at that side window.
The SOG does seem to help with better control of effluent smell and breakdown. The original units sell around the $200 to $360 ours only cost for flexible hose, 60mm computer fan, 12volt switch, an electrical junction box for fitment of a Charcoal filter/fan and an external plastic vent louvre - all for a cost around $60.
I have spoken with others who have the original SOG fitted and have never heard a derogatory remark about the unit and it's operation, they would definitely fit one again as I would also.