fitting a holding tank

Falcoron

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I am going to fit a holding tank as the regulations state that they must be fitted and i think its also the right thing to do.
my boat, which is not in the water didn't have one so will have soon.
Can anyone look at my diagram and let me know if this is ok please?

The head and tanks are below the water line so i know i must put in an anti siphon loop with an auto vent to stop siphoning.
The tanks are not on top of each other but 1 is on port and other is on s/board under rear storage compartment.
The fresh water system has a good pump and an accumulator tank.
i have all new tanks and fittings.
head.JPG
 
Whereabouts are you located that needs a compulsory holding tank?

What you show is not the conventional way of plumbing a holding tank. Usually the overboard outlet is retained and the waste is diverted to the tank when required. Just having a deck pumpout and all waste held in the tank and being solely reliant on external pumpout is very unusual.
 
My holding tank setup is that each heads has a seacock that can be diverted to for 'direct exit'. I have hoses from each heads to the tank. The tank itself has two outlets. One goes to a deck fitting (the same fitment as the diesel fillers etc) for suction pumping at a pumping station. The other goes through a macerator pump (which has a switch on the fuse panel) that through a vented loop goes to a seacock so when you're out at sea you can empty the tank at sea.

The top of the tank has a level sender which does the obvious..

That's about it. It's not the most complicated thing on earth but incredibly yucky when I had to replace a failed outlet pump and hose.... But that's another story.
 
Whereabouts are you located that needs a compulsory holding tank?

What you show is not the conventional way of plumbing a holding tank. Usually the overboard outlet is retained and the waste is diverted to the tank when required. Just having a deck pumpout and all waste held in the tank and being solely reliant on external pumpout is very unusual.

Inland waterways in Ireland (Erne Shannon system) have a £1000 fine if a boat has no holding tank, if there is one with a valve for dumping into the water it must be made redundant so you cannot use, so no point putting one in.

I'm not sure if what i have on the diagram is correct or not so the reason I'm asking here.
But i got the letter from Inland waterways when i registered the boat last week with this warning.
 
My holding tank setup is that each heads has a seacock that can be diverted to for 'direct exit'. I have hoses from each heads to the tank. The tank itself has two outlets. One goes to a deck fitting (the same fitment as the diesel fillers etc) for suction pumping at a pumping station. The other goes through a macerator pump (which has a switch on the fuse panel) that through a vented loop goes to a seacock so when you're out at sea you can empty the tank at sea.

The top of the tank has a level sender which does the obvious..

That's about it. It's not the most complicated thing on earth but incredibly yucky when I had to replace a failed outlet pump and hose.... But that's another story.
yeah at sea is ok but not for inland waterways here on the Erne Shannon system
.
 
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Why not fit a caravan style toilet? Don't require a pump out point, just somewhere you can empty the portable cassette unit.

Even though you may have all the bits to fit a holding tank, it is a lot of work.
 
yeah at sea is ok but not for inland waterways here on the Erne Shannon system
.
But it still has the pump-out option on the deck. You don't have to pump out at sea. The system gives you the choice of either option depending on where you stick yer boat!
 
Why not fit a caravan style toilet? Don't require a pump out point, just somewhere you can empty the portable cassette unit.

Even though you may have all the bits to fit a holding tank, it is a lot of work.
No thanks had a caravan and that’s a smelly chore emptying
 
I am going to fit a holding tank as the regulations state that they must be fitted and i think its also the right thing to do.
my boat, which is not in the water didn't have one so will have soon.
Can anyone look at my diagram and let me know if this is ok please?

The head and tanks are below the water line so i know i must put in an anti siphon loop with an auto vent to stop siphoning.
The tanks are not on top of each other but 1 is on port and other is on s/board under rear storage compartment.
The fresh water system has a good pump and an accumulator tank.
i have all new tanks and fittings.
View attachment 125983

If you are going into a holding tank and flush water supply from a domestic water tank there is NO NEED for anti syphon valve.
If you have no intention of wanting to ever discharge overboard don't fit a diverter valve, not needed.
I've fitted lots of holding tank systems, the best simple electric freshwater flush toilet is the Jabsco quiet flush with the solenoid valve so the current domestic pump pushes the water to the toilet. Jabsco 37045-4192 - QUIET FLUSH ELECTRIC TOILET Fresh water flush models, Regular bowl size, 12 volt dc / Electric Toilets / Toilets / Marine Toilets / Marine / Xylem JabscoShop - Jabsco & Rule Pumps and more - from the experts

The compact bowl is good if short on space.

Stainless steel holding tanks are the best, no smells.
Wema gauge and sender.
Fit a Vetus no smell filter in the vent line to stop outside smells when the toilet is being flushed.
Fit high quality hoses like the Vetus SA Hose.
Nice large vent of 19mm or 25mm diameter.
 
Thank you BB1
Just what I wanted.
if you look at the diagram you will see I have a jabsco electric silent flush toilet. However it was fitted already and is plumbed to pump overboard.
I won’t be fitting a diverter valve, as you say I’m feeding from fresh water tank.
I’m not sure my toilet has the solenoid how do I tell and can it be fitted if I don’t?
I also have new good quality hose.
I’m surprised I don’t need an anti siphon as the toilet is under the waterline. Every supplier bar non has told me this?
My new tank is plastic not stainless but will be very well vented which helps reduce the sulphur smells building and I will have a charcoal vent filter fitted as well
 
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A siphon valve is to stop water coming in from outside, you won't have any contact with external water.
The toilet has a non return valve fitted in the line to the holding tank.
Does the current toilet feed from your domestic water supply? If it does it should have the solenoid valve in the flush feed hose, if it supplies flush water from the sea/river it will have a pump.
You can buy the solenoid as a spare part.

If you are currently pumping from sea/river you may have the old style toilet with a twin pump on the back that pumps in and out at the same time.

Do you have a single switch or one where you can fill the bowl only?
 
I am going to fit a holding tank as the regulations state that they must be fitted and i think its also the right thing to do.
my boat, which is not in the water didn't have one so will have soon.
Can anyone look at my diagram and let me know if this is ok please?

The head and tanks are below the water line so i know i must put in an anti siphon loop with an auto vent to stop siphoning.
The tanks are not on top of each other but 1 is on port and other is on s/board under rear storage compartment.
The fresh water system has a good pump and an accumulator tank.
i have all new tanks and fittings.
View attachment 125983
here are some other ways of designing a system Holding Tank Plumbing and Layouts | Tek-Tanks

www.solocoastalsailing.co.uk
 
A siphon valve is to stop water coming in from outside, you won't have any contact with external water.
The toilet has a non return valve fitted in the line to the holding tank.
Does the current toilet feed from your domestic water supply? If it does it should have the solenoid valve in the flush feed hose, if it supplies flush water from the sea/river it will have a pump.
You can buy the solenoid as a spare part.

If you are currently pumping from sea/river you may have the old style toilet with a twin pump on the back that pumps in and out at the same time.

Do you have a single switch or one where you can fill the bowl only?
Thanks again BB1,
Yeah this is the older type and the water was pumped from the outside. I want to plumb differently like above.

This is what i have now.
tpump.JPG
 
Thanks again BB1,
Yeah this is the older type and the water was pumped from the outside. I want to plumb differently like above.

This is what i have now.
tView attachment 126027
Mmmm...... Never seen one of these drawing from a water tank, I would seriously think about replacing this toilet with a later freshwater flush type.
Jabsco 37045-4094 - QUIET FLUSH ELECTRIC TOILET Fresh water flush models, Regular bowl size, 24 volt dc / Electric Toilets / Toilets / Marine Toilets / Marine / Xylem JabscoShop - Jabsco & Rule Pumps and more - from the experts
I presume that you could take the feed from the water tank, not in the water hose after the domestic water pump. This toilet is really only set up for river/sea water flush, talk to jabscoshop.com
 
Mmmm...... Never seen one of these drawing from a water tank, I would seriously think about replacing this toilet with a later freshwater flush type.
Jabsco 37045-4094 - QUIET FLUSH ELECTRIC TOILET Fresh water flush models, Regular bowl size, 24 volt dc / Electric Toilets / Toilets / Marine Toilets / Marine / Xylem JabscoShop - Jabsco & Rule Pumps and more - from the experts
I presume that you could take the feed from the water tank, not in the water hose after the domestic water pump. This toilet is really only set up for river/sea water flush, talk to jabscoshop.com

BUMMER excuse the pun!
Never a cheap fix these fecking boats.
yes this was the set up and it pumped water from outside, so this is useless to me now? GRRRRR getting nowhere fast with this refurb.
thanks again.
 
Mmmm...... Never seen one of these drawing from a water tank, I would seriously think about replacing this toilet with a later freshwater flush type.
Jabsco 37045-4094 - QUIET FLUSH ELECTRIC TOILET Fresh water flush models, Regular bowl size, 24 volt dc / Electric Toilets / Toilets / Marine Toilets / Marine / Xylem JabscoShop - Jabsco & Rule Pumps and more - from the experts
I presume that you could take the feed from the water tank, not in the water hose after the domestic water pump. This toilet is really only set up for river/sea water flush, talk to jabscoshop.com

BB1 thanks again for your help, i contacted jabsco and they told me this is indeed a pressurised fresh water toilet and i should have a solenoid somewhere in the system. I just found it behind the head unit low down.
So all i need to do is divert from dumping overboard to a holding tank which should be pretty straight forward i would think. if i place a diverter valve in and lock off the outside exit would that be ok?
 
BB1 thanks again for your help, i contacted jabsco and they told me this is indeed a pressurised fresh water toilet and i should have a solenoid somewhere in the system. I just found it behind the head unit low down.
So all i need to do is divert from dumping overboard to a holding tank which should be pretty straight forward i would think. if i place a diverter valve in and lock off the outside exit would that be ok?

Yep, will be fine,
 

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