Heads/tank outlet

[dgadee]

Planning to have the toilet pump out to a hull outlet and the black water tank pump out to the same hull fitting. Can I just use a y piece before the hull fitting or do I need a valve to switch between the two? That is, do pumps stop the flow in reverse?

 

[Baggywrinkle]

A black water tank holds the contents of your toilet. A grey water tank holds shower and sink water.

Do you mean black or grey water? ... obviously the toilet is black water.

Most holding tanks on modern boats are above the waterline, the toilet pumps into the top of the tank, and it is prevented from draining into the sea by a manual valve at the bottom. Open the valve and the tank empties into the sea.

Grey water on boats normally goes straight overboard via a pump in the shower floor or directly from a sink to a through hull valve.

What you need to know about a yacht's black water waste tank - Yachting Monthly

 

[tillergirl]

Dead simples provided you have a Lavac

Holding Tank Drawing 1 by Roger Gaspar, on Flickr

The holding tank is just the other side of the forward bulkhead (to the right).

 

[dgadee]

Black water - holding tanks.

On my Dehler the tank is gravity and empties out of the bottom. It has a valve which is opened when you want to empty it (and blocks off the toilet to the hull fitting). On this one which I am planning to install it will be pumped from the top via an internal stand pipe.

This will be my third black water tank installation. The second one pumped out to its own skin fitting and worked well. On this third one I am thinking of combining the two methods and saving a skin fitting (marelon ones are about £150) and a diverter valve (£70).

Divertor valve at toilet to either overboard/tank. Pump from tank standpipe straight to existing hull fitting or to diverter valve then existing hull fitting? If I don't have a diverter valve at the outlet will waste be pumped back to the toilet/tank?

 

[dgadee]

Dead simples provided you have a Lavac

Holding Tank Drawing 1 by Roger Gaspar, on Flickr

The holding tank is just the other side of the forward bulkhead (to the right).

You have two diverter valves. Pumped output from tank goes to a diverter valve at hull fitting.

 

[PCUK]

Planning to have the toilet pump out to a hull outlet and the black water tank pump out to the same hull fitting. Can I just use a y piece before the hull fitting or do I need a valve to switch between the two? That is, do pumps stop the flow in reverse?

Yes, That's all you need.