Proper job

[Sammo]

With my refit coming to an end I have learnt on here that the toilet flushing can`t be connected to the water tanks.
I have 2 toilets a Blake Victory and a Baby Blake, there are two 50 gallon s/steel water tanks and I have connected an off take from the crossover on the tanks to the flush pumps on the toilets.
So do I really have to go to the time and trouble to change it?
I look at my household toilet system and the water main that goes to my sink taps also goes to my toilet flush so I dunno.
To change it now is a lot of trouble but I don’t particularly want to murder my crew.

What to do?

…..

 

[MoodySabre]

On your household water there is no direct pipework connection from the loo to the tap because of the cistern.

I think that there is a distinct risk of contamination of the domestic water supply. If you do not want to introduce a skin-fitting for the loo water intake (as is normal) then you could always disconnect the two tanks and have one for flushing and one for domestic use.

 

[pete]

On your toilet at home there will be an air break between the ballvalve and the water in the cistern (even if you have a pipe from the ballvalve dropping into the water to quieten things down)
that will prevent cross contamination and back syphonage.
You could perhaps fit a double check valve in the supply to the heads which is a fitting which has 2 one way valves built into it but it will increase the resistance on this pipe considerably.

Pete

 

[pvb]

Why?

With such small fresh water tank capacity, why on earth would you want to flush your toilets with fresh water?

 

[Sammo]

Re: Why?

There are 2 tanks 50 gallons each so 100 gallons in all. Plenty of water.

There are advantages to using freshwater for flushing as sea/riverwater can be discoloured and/or smelly.

I just cant find a precise explanation as to why you shouldn’t connect your flush pump to the water system rather than saying “there is a distinct risk of contamination.”


I really don`t want to go to the time and trouble of changing it all and drilling two more holes in the hull if it is not necessary.


……..

 

[Norman_E]

Alternative and safe solution woud be to isolate the two tanks, one for domestic supply and one for toilet flushing, if you must use fresh water for the heads.
EDIT. THe way heads pumps work there is a possibilty of a small amount of effluent getting past the inlet valve back in to the supply pipe, That would allow bacteria to migrate in to the tank

 

[jh2005]

There was a Gemini Catamaran at the London Boatshow which has 2 diverter valves specifically to flush the heads with fresh water. I think it was intended for rinsing the system through rather than general use.

 

[MoodySabre]

Re: Why?

Norman has it. The discharge and the flushing water both use the same piston in the pump. The flushing water remains in the inlet pipe and is therefore in very close proximity to the piston. Bacteria walks! And once the water in the inlet is contaminated so will be the main tanks.

 

[Norman_E]

Re: Why?

One further thought, If you do decide to separate the water supply, you can always add a bit of Milton whenever you top up the toilet flush tank.

 

[Sammo]

Re: Why?

I agree with what you are saying but that doesn’t apply to the toilets I am using which have 2 pumps, 1 for flushing and another completely independent one for discharge.

As you see in the picture of the baby blake (the victory is the same design but larger) the pump to the right with the lever, pumps out the bowl. Slightly to the left of it with the T handle is the flush pump that flushes fresh water into the top of the bowl so basically the waters don`t mix.
As they are two separate systems I wonder if it is acceptable to connect the flush pump to the fresh water tank?


……

 

[MoodySabre]

Re: Why?

I'm not a plumber and I can see your point - I just wouldn't want to drink your tap water! If there's any kind of risk of getting ill at sea then I'd like to avoid it. Others might be OK with your suggestion - just a gut feeling (pardon the phrase).

 

[neil_s]

It seems to me that all you need to match the isolation between the toilet bowl and the fresh water tap that exists in the average home is a non return valve between your fresh water tank and the flush pump of your baby blake. Flushing with fresh water will make your loos a lot less smelly and easier to look after, a thing those Portapotti users amongst us well know!

Neil


Neil

 

[Vara]

Surprised Headmistress hasn't chipped in.
Must be on Holiday!
Quote from her authoritative tome.

"connecting any raw water flush toilet to the onboard fresh water system is NOT an option"

If you want any more you'll have to wait for HMtss or buy the book.

 

[Sammo]

I would be glad to hear what Peggy has to say but I would suspect that as a professional she won`t go out on a limb.
However as I see it the two waters don`t mix so if the water tank is treated it should be OK for washing showers ect.(we always use bottled water for drinking anyway)


…….

 

[nigelhudson]

I always ensure that the last flush before leaving the boat is with fresh water. That means the discharge pipe has freshwater in it rather than seawater. I have a length of hose in the heads that I connect to the basin tap to fill the bowl. With the inlet cock closed I pump out the bowl before closing the outlet cock. The result is much fresher smelling heads even if left for several weeks.