On another thread that went all High School and maths and other bad memories
Blissonwheels gave this reply
Gooday,
I fitted 2 lengths of 6 inch PVC stormwater pipe under our caravan, linked together and capped at both ends, one is slightly longer by about 3 inches than the other due to other fittings, they fit between the chassis rails at the rear. My calculations were I can hold 52 litres. I have a ball valve so I can divert from ground to grey water tanks, included a breather, and have a Camlok fitting to drain when necessary.
Works well for us, got one pice of pipe for nothing, the other I paid $5-00 for, the most expensive parts were the end caps at $19-00 each
Bliss On Wheels
My interest is only for the kitchen sink, so some storm water pipe will be big enough, but of all our grey water the sink is potentially the worst for nasty/smelly bacteria breeding. What sort of trap do people use to prevent the smell coming up the sink pipe or the vent under than van just being a sad smelly pong all the time. How often do people empty their tank. I would do all of what Blissonwheels has done, but is smell and issue.
I have bent flex hose on the kitchen sink and hand basin with a standard waste trap for the shower base. The hose is just looped to form a horizontal " S " shape. Some cable ties help with support.
Only problem with the s trap is that if the van sits around for long enough not used the water evaporates , more than likely though you would have emptied the tank well b4 then .
Thanks people, the oneway valve will be my choice, and as no-one actually says so, I assume the alternative is an unpleasant odour that civilised travellers do not talk about.
Sarge9 I have 2 x 150mm PVC pipes hooked up as my GW tank, and while it takes all my drains (sink, washing machine, shower) wit no S traps, there is no stink or collection of crud to cause it like store bought units as I have screw on end caps so I can regularly flush the tanks, drain hose connected to a gate valve for when a GW holding tanks is not needed (which is most times) I have used this idea on 2 vans and fitted some to friends rigs and no stink reported.....I have a one way on the shower drain but thats only to stop back flow in case I overfill the tanks and the breather gets blocked.
S traps and such are needed with the converted water tanks as you never get the crud out which ends up blocking the drain valve and S trap....
Thanks BM.... I will have removable end cap/s, but will be limited in the length of pipe I can use as I have to go parallel to the chassis or put a tyre on it and make it a tandem. Much too close to the ground to copy your set up.
