Sog toilet vents .

Ours has housekeeping daily and still stinks
hi guys . ours after 3 months away i must admit does smell of a urinal & we have 2 fan's on our toilet plus tab's . my take on the problem is i think it get's in to the plastic so when back home we give it a good soak right to the top with washing up liquid . then empty & leave to dry with the blade open works for us .cheyenne
 
hi guys . ours after 3 months away i must admit does smell of a urinal & we have 2 fan's on our toilet plus tab's . my take on the problem is i think it get's in to the plastic so when back home we give it a good soak right to the top with washing up liquid . then empty & leave to dry with the blade open works for us .cheyenne
It's a strange one we have never had problems until this new to us van that has a sog.

Ours has 2 fans one under cassette to blow air in and one to suck it out once flap is open..
Boy it stinks most of the time, going to change bits see if that helps, will get the bleach out today..thanks
 
It's a strange one we have never had problems until this new to us van that has a sog.

Ours has 2 fans one under cassette to blow air in and one to suck it out once flap is open..
Boy it stinks most of the time, going to change bits see if that helps, will get the bleach out today..thanks
That doesn’t sound like a normal SOG system which has one fan that only operates with the blade open. Have you got both a Thetford and a SOG? In which case they may be competing and causing your problem.
 
That doesn’t sound like a normal SOG system which has one fan that only operates with the blade open. Have you got both a Thetford and a SOG? In which case they may be competing and causing your problem.
Yes ..
There is a fan in base under cassette. Which blows air in after you use it ,for about 2mins.
Then sog fan that works when you open flap which vents to out side van.
 
A daft thought perhaps, but is the overun fan blowing the SOG extracted air back in 🤔🤔. Can you disconnect the overun fan and try it on SOG only?
 
Yes ..
There is a fan in base under cassette. Which blows air in after you use it ,for about 2mins.
Then sog fan that works when you open flap which vents to out side van.
The SOG works on the principle that the fan draws air down through the open flap from the bathroom so that smells can not escape from the cassette in the opposite direction. If there are other devices connected perhaps the SOG fan is pulling air in through them rather than through the open flap, in which case it will not work.

The Thetford one seems to try to ventilate the the cassette after use but this seems a hopeless task because the liquid source of the smells is still there.

I would remove the Thetford fan assembly from below the cassette and see if the SOG works better without it.
 
Might also be worth checking that the SOG has been installed properly. It is possible that with two different systems having different requirements that neither has been put in properly and neither works properly.
 
Might also be worth checking that the SOG has been installed properly. It is possible that with two different systems having different requirements that neither has been put in properly and neither works properly.
All fans running correctly .
I now understand how the twin fans work .
Which are both factory fitted on build.
Autotrail frontier vans.

First the out side fan sucks air out when flap opened..
Close flap it stops .
Second fan then cuts in blowing air in to cassette and vents through to outside .using pipes of fan 1 .
 
It's isn't something I'd have fitted but it was a good selling point on two vans we bought to flip, and I though it was a good design and worked well but a bit over priced IMO, Not see the Dometic/Thetford version.
 
hi guys . van's on storage so no photos of our system but we have 2 thetford & sog but if you you look at the sog system we had the same problem turned out to be the corrugated pipe had a split with opening & closing the door ( hard to find ) . i have fitted these . cheyenne
hi guys .just check out incase you have not seen the first few reply's .cheyenne P.S make sure you expand to see the full 3 items
 
hi guys .just check out incase you have not seen the first few reply's .cheyenne P.S make sure you expand to see the full 3 items
Yes did look.thanks
Ordered filter 2 day's ago arrived fitted.
Just waiting on new flap meck and seals.

Bleached cassette out looks spotless .
 
but it was a good selling point
Wouldn’t be good selling point for me. I would expect a factory fitted option to be roof vented (no filter needed), the door vent option is appropriate for retro fitting. Also I can see no point whatsoever in blowing air into the cassette, it might blow a few smells out while running but once it stops the smell inside the cassette will build up to the same concentration almost immediately. If the blade seal is less than perfect the positive pressure inside the cassette is likely to push smells back into the bathroom.
 
Wouldn’t be good selling point for me. I would expect a factory fitted option to be roof vented (no filter needed), the door vent option is appropriate for retro fitting. Also I can see no point whatsoever in blowing air into the cassette, it might blow a few smells out while running but once it stops the smell inside the cassette will build up to the same concentration almost immediately. If the blade seal is less than perfect the positive pressure inside the cassette is likely to push smells back into the bathroom.
Dunno what you've read but it doesn't blow air into the cassette, it sucks air out as soon as the vent lever is moved, if it blew in you would have to get out of the van a bit quick :D :D

I agree sort of with the roof vent, but I know not whether the reasonably fresh aroma is heavier or lighter than air, is it methane at that point? if so go up a chimley, if not let it fall to the ground.
 
Dunno what you've read but it doesn't blow air into the cassette, it sucks air out as soon as the vent lever is moved, if it blew in you would have to get out of the van a bit quick :D :D
Well the thetford fitted fan, blows air in to cassette .that's why i am changing flap and seal..
 
Dunno what you've read but it doesn't blow air into the cassette, it sucks air out as soon as the vent lever is moved, if it blew in you would have to get out of the van a bit quick :D :D
OK but with the fan below the cassette how does the sucked air get to the outside?
I agree sort of with the roof vent, but I know not whether the reasonably fresh aroma is heavier or lighter than air, is it methane at that point? if so go up a chimley, if not let it fall to the ground.
I have no problem with my unfiltered roof vent. Have never noticed any smells outside the motorhome and the pong from the cassette never comes inside.
Well the thetford fitted fan, blows air in to cassette .that's why i am changing flap and seal..
When does the Thetford fan cut in and cut out?
 
Well the thetford fitted fan, blows air in to cassette .that's why i am changing flap and seal..
hi . i might be talking rubbish here but i have fitted 4 sog systems & the sog is supposed to take the air out not in . the best way is light a cigarette
& see if the fan takes the smoke out through the filter which it should do if not the wires have been connected wrong . cheyenne
 
OK but with the fan below the cassette how does the sucked air get to the outside?

I have no problem with my unfiltered roof vent. Have never noticed any smells outside the motorhome and the pong from the cassette never comes inside.

When does the Thetford fan cut in and cut out?
hi guys. the Thetford has a replacement control panel & the sog fan is wired in to that so both fans come on at the same time & run's on for 5 minuets .cheyenne
 
Having had to fix one and test it I know how it works and is about as basic as it gets really, drill hole in cassette emptying pipe/tube near to the cap, then a tube up to fan in the cassette locker door, you fit a microswitch to be triggered by the flap mechanism when you want to empty the bowl, this turns on a fan which sucks the aroma out of the cassette and through a charcoal filter in the cassette door and away to atmosphere.

It has a charcoal filter inside the door next to the fan to reduce the aroma, if it sucked in it could inflate/pressurise the cassette, it would do no good and the cassette could vent all over you when you opened the bowl.

 
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Having had to fix one and test it I know how it works and is about as basic as it gets really, drill hole in cassette emptying pipe/tube near to the cap, then a tube up to fan in the cassette locker door, you fit a microswitch to be triggered by the flap mechanism when you want to empty the bowl, this turns on a fan which sucks the aroma out of the cassette and through a charcoal filter in the cassette door and away to atmosphere.

It has a charcoal filter inside the door next to the fan to reduce the aroma, if it sucked in it could inflate/pressurise the cassette, it would do no good and the cassette could vent all over you when you opened the bowl.

The SOG is straight forward and effective, it is the operation of the Thetford fan that is a mystery to me.
hi guys. the Thetford has a replacement control panel & the sog fan is wired in to that so both fans come on at the same time & run's on for 5 minuets .cheyenne
If the Thetford fan is blowing into the cassette then with both running at best they will cancel each other out but the Thetford fan looks bigger so it will just blow the smells out of the open blade. If they are both sucking from different points it ought to work but does it just create confused air currents and fail to do the job properly. Then with the blade closed and a 5 minute overrun both fans are sucking at a closed chamber, presumably achieving s_d all. You can’t vent a closed chamber it would be like sucking on a drinking straw with your finger over the other end.

SOG devised a simple and effective device. Blade opens fan sucks air out of the cassette drawing fresh air in through the open blade hole which prevents smells escaping into the living area. Blade shuts, job done, fan switches off. I know this works I have one.

@Mr and Mrs Tupcox have a sophisticated system with 2 fans from 2 different systems which from their own accounts clearly does not work effectively. Was this idea developed by a clever engineer or someone in marketing who thought it would look good in the brochure?
 

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