Toilet anti-syphon?

purplerobbie

purplerobbie

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Would anyone have a diagram on how a toilet should be fitted regarding the hoses?
Mine will back fill ever so slightly but only every now and then?
It has a pipe that does come over the waterline slightly but should it have some sort of anti-syphon on it? If the boat was on the same tack as the toilet side then all the hoses would be under the waterline? Does the pipe have to come over the waterline on all tacks?
The boat has a 12 volt toilet with a macerator and someone said it won't need any of this? Can't see that being true?
 
Back filling ever so slightly is usually due to the Joker valve not completely closing. It could be because the toilet wasn't adequately pumped and some tissue or soil remains at the valve preventing it from closing.
 
If you have no loop of any sort you are relying on the joker valve to keep water out of the toilet. It is normal to have a loop on the outlet side, going up to a point higher than the water will ever reach on the appropriate tack. If the toilet is below the normal water level there should also be a loop on the inlet side but it is customary for this not to be fitted otherwise.

As Talulah says, water in the bowl, usually smelly, is a sign that the joker valve is leaking. Other than solids between the lips it is quite common for some salts to accumulate here, also preventing full closure.
 
Hi

This is my anti sysphon system which has worked fine for the last four years, the toilet bowl is almost below the water line level and both sea cocks are Blakes.

The other valve at the top is to a bilge pump but is also shut when under sail.

Mike
View attachment 29617
 
Caer Urfa said:
Hi

This is my anti sysphon system which has worked fine for the last four years, the toilet bowl is almost below the water line level and both sea cocks are Blakes.

The other valve at the top is to a bilge pump but is also shut when under sail.

Mike
View attachment 29617
Click to expand...

Mike only does things the right way and the photo is a full belt and braces approach showing exactly what most people say you should have. However I personally don't like it and I'm aware that almost everyone on here will disagree with me but the reason I don't like it is aesthetic. I've seen a number of installations like Mike's and on the Kipper we rejected that approach, no anti syphon valves, much lower and shorter loops but still above the waterline - the toilet rim is just above the w/l. We put inline ball valves, when we leave the boat or go out in heavy weather we close the ball valves, takes 5 seconds. The result is a much prettier installation that would completely fail to impress those who do things properly. I still think we're safe, just not as fit-and-forget safe as the picture but we didn't want those pipes:(
 
Lazy Kipper said:
Mike only does things the right way and the photo is a full belt and braces approach showing exactly what most people say you should have. However I personally don't like it and I'm aware that almost everyone on here will disagree with me but the reason I don't like it is aesthetic. I've seen a number of installations like Mike's and on the Kipper we rejected that approach, no anti syphon valves, much lower and shorter loops but still above the waterline - the toilet rim is just above the w/l. We put inline ball valves, when we leave the boat or go out in heavy weather we close the ball valves, takes 5 seconds. The result is a much prettier installation that would completely fail to impress those who do things properly. I still think we're safe, just not as fit-and-forget safe as the picture but we didn't want those pipes:(
Click to expand...
We've got most of those pipes but they are all hidden inside lockers!
 
Assuming that it is an electric toilet that you are having problems with I may be able to help. I inherited an elec toilet with the boat that know have and I didn't know at the time that it was a bad instalation I also had probs with the bowl backfilling to much but I eventually realised that the problem was that the inlet flushing water was coming in faster than the waste was exiting. This was caused by a build up of limescale deposits inside the waste hose, effectively reducing the internal bore. At least twice a year I have to remove the hose, lay it along a solid surface and tap along its length with a heave hammer to loosen it and then flush it out with mains pressure from a hosepipe remember to hang the open end into the harbor. I have tried dosing the hose with vinigar in situ and it does help a bit. I have a plan to fit a bigger size hose (38mm)
Secondly for safety and efficiently you should have antisiphon valves at the top of vented loops (above waterline at all times). The one on the inlet side is problematic as the pump is sucking rather than pushing and a regular antisyphon valve would not work. I fitted a normally open solenoid valve which is energised (closed) when the pump is operated (wired to the switch). I hope experiences help you in some way.
 
I guess if the toilet rim is above the w/l but the inlet point is below then technically I need anti-syphon loops in case the loo breaks apart but we need the cupboards for stuff and I couldn't face looking at all those loops, like a nest of snakes, plus you pump for ever to clear and there's all that standing water ready to start smelling. Ho hum, each to their own.
 
Lazy Kipper said:
Mike only does things the right way and the photo is a full belt and braces approach showing exactly what most people say you should have. However I personally don't like it and I'm aware that almost everyone on here will disagree with me but the reason I don't like it is aesthetic. I've seen a number of installations like Mike's and on the Kipper we rejected that approach, no anti syphon valves, much lower and shorter loops but still above the waterline - the toilet rim is just above the w/l. We put inline ball valves, when we leave the boat or go out in heavy weather we close the ball valves, takes 5 seconds. The result is a much prettier installation that would completely fail to impress those who do things properly. I still think we're safe, just not as fit-and-forget safe as the picture but we didn't want those pipes:(
Click to expand...

Ye of little faith !

This is how it normally looks;)


View attachment 29759 View attachment 29758
 
Lazy Kipper said:
That's quality goretex that is .
Click to expand...

:) Sorry mate your wrong again!

That's my super dry offshore sailing jacket bought three years ago from ALDI for £25

That jacket is one of the best and cheapest things I have bought for the boat and if they have any more for sale I will be the first in the queue to buy another one!

The other best thing for winter sailing was my 'Ninja hat' for £2.50, where from? the best yacht chandlers again Aldi :D

View attachment 29814
 
Lazy Kipper said:
Mike only does things the right way and the photo is a full belt and braces approach showing exactly what most people say you should have. However I personally don't like it and I'm aware that almost everyone on here will disagree with me but the reason I don't like it is aesthetic. I've seen a number of installations like Mike's and on the Kipper we rejected that approach, no anti syphon valves, much lower and shorter loops but still above the waterline - the toilet rim is just above the w/l. We put inline ball valves, when we leave the boat or go out in heavy weather we close the ball valves, takes 5 seconds. The result is a much prettier installation that would completely fail to impress those who do things properly. I still think we're safe, just not as fit-and-forget safe as the picture but we didn't want those pipes:(
Click to expand...

Right plumbing nightmare!!
 
Am I doing something wrong?

As I don't have a anti-siphon-loop .... the boat never came with one ..... I've fitted a new Jabsco & still didn't install a loop ....used-to always shut the hull valves when sailing/motoring .... forgot once & everything was fine .... so I only shut all valves (apart from cockpit drains) when I leave the boat. :confused:
 
OGITD said:
As I don't have a anti-siphon-loop .... the boat never came with one ..... I've fitted a new Jabsco & still didn't install a loop ....used-to always shut the hull valves when sailing/motoring .... forgot once & everything was fine .... so I only shut all valves (apart from cockpit drains) when I leave the boat. :confused:
Click to expand...

Just means you're relying on the cheap crappy little rubber valves inside the toilet pump to keep the water out of your boat. Obviously they succeeded on this occasion, being fairly new. I wouldn't like to rely on it long-term.

EDIT: Here's a story about a boat that sank at her moorings. Only two candidates for the water intake (see the penultimate paragraph) - bilge pump and toilet. One of these, with nothing broken or changed, one day started siphoning into the boat, and down she went.

http://www.yachtmollymawk.com/2011/02/the-fall-and-rise-of-duck/

Pete
 
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If the rim is a few inches or more above the w/l then on a mooring you're safe - boats sinking due to toilets flooding are as rare as scare stories can get, but I agree that a rim below the waterline absolutely requires an anti syphon loop and valve. Hopefully done neater and less obtrusive than some I've seen.
 
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