Bigger grey water drain tap

Southdown Motorhomes for the tap. It's a fairly standard type of thing, probably available at many Caravan/MH dealers or on the net.

Yes those small bore valves must be a real pain. My pipework is approximately 30mm-35mm into and out of the tank and a decent size valve.so no tank draining issues. The one puzzle I have is the flow from the kitchen sink.It is usually slow until I give it a couple of very light pumps with a traditional sink plunger. This works for a short time then slows up again. We're very careful about what goes down the plughole i.e. no fat or grease so why does it run freely then slow up again so quickly? Any answers anyone?

If there is flexible pipe in the run to the outlet then possibly it sags and they hold water which slow down the flow and a plunger will give temporary increase in flow

a lot depends on the pipe run, our centrally sited kitchen and washroom drain directly downwards into a centrally mounted waste water tank via totally seperate pipes for the kitchen sink, the washroom sink and the two shower drains.....each has a seperate entry spigot on the waste tank....not surprisingly, the water drains quickly from each source....even on a slight slope.

i can see that it is tricky if the washroom isn't the rear and the tank is at the front....by why would any one design it that way?

re: the tank drain, our tank has a large bore drain with an internally mounted valve to avoid freezing of the water stored when a tap is on the end of a pipe. a small extra length of flexible pipe allows for a good aim with awkwardly sited drains.

I have exactly the same problem. I have an Elldis Accordo and the blue water drain tap which is just the same as your grey water tap has become so stiff that I can't turn it anymore. I've done some research and I think it's a speedfit system. These fittings are available on Screwfix. I'm going to replace the tap with a shut off valve. I'll also lengthen the pipework a bit to make it easier to access. How did you get on with yours?

oooerr ,  You haven't  noticed the dates of the previous postings have you ??   18/6/2019 !!

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