guyd
Guest
The air valve stops the glug glug effect you get when emptying a bottle - its quite cleverly designed, and you never see anything, apart from when it comes out of the spout into the bog. The 'in' valve self seals as you remove the cassette from the vehicle.
There are types that you dont use a cassette - but they are horribly expensive - the thetford aqua magic V is 200 quid - plus fitting, plus a new black water tank under the vehicle...... plus emptying valve - and you have to make sure theres a emptying manhole cover you can get to and drive over.... Then open this, looking at everyone elses 'stuff' and dump the contents....
There are types that you dont use a cassette - but they are horribly expensive - the thetford aqua magic V is 200 quid - plus fitting, plus a new black water tank under the vehicle...... plus emptying valve - and you have to make sure theres a emptying manhole cover you can get to and drive over.... Then open this, looking at everyone elses 'stuff' and dump the contents....