Syphon breaks

[johnjfrake]

I am planning the potential installation of an SL400 in the bow cabin of my Folksong 26. Currently no bog or through hull fittings for a loo. The cost of 2 through hull fittings (built in valves), hose, syphon breaks breathers etc. amount to about £200.00. The Folksong does not have a lot of freeboard. This question is about syphon breaks. How essential are they? If I run the hoses via loops to a syphon break in the forecabin there is an awfull lot of hose and clips and breaks etc. visible and making storage awkward. If I don't then I am very dependant on closing the inlet and outlet valves after business for the safety of the boat and crew. How effective will a syphon break be given the boat sails in a fairly leany overy mode and it is difficlt to keep the break valve above the water line on all points of sail? I am sorely tempted to have a Thetford or similar, just not sure how much of a nuiscance emptying them is? Also how do they cope with leany/overy type sailoring? How easy are they to bolt donw and do the fittings cope with stress?

Any opinions/facts on either issue welcome!

Thanks

 

[Otter]

Great loops of toilet hose are horribly unsightly, I've never heard of a yacht sinking due to water siphoning. For extra safety we fitted inline ball valves to avoid the hassle of turning off skin fittings - such a big hassle that we often don't bother with them. The ball valves are just next to the toilet so as easy to use as the Jabsco twist and lock which in any case hasn't failed.

 

[sailorman]

I am planning the potential installation of an SL400 in the bow cabin of my Folksong 26. Currently no bog or through hull fittings for a loo. The cost of 2 through hull fittings (built in valves), hose, syphon breaks breathers etc. amount to about £200.00. The Folksong does not have a lot of freeboard. This question is about syphon breaks. How essential are they? If I run the hoses via loops to a syphon break in the forecabin there is an awfull lot of hose and clips and breaks etc. visible and making storage awkward. If I don't then I am very dependant on closing the inlet and outlet valves after business for the safety of the boat and crew. How effective will a syphon break be given the boat sails in a fairly leany overy mode and it is difficlt to keep the break valve above the water line on all points of sail? I am sorely tempted to have a Thetford or similar, just not sure how much of a nuiscance emptying them is? Also how do they cope with leany/overy type sailoring? How easy are they to bolt donw and do the fittings cope with stress?

Any opinions/facts on either issue welcome!

Thanks

I believe the SL 400 to be obsolete & spares hard to find, so suggest some investigation.
I have a Lavac, they cost more than some toilets but are very simple & easy to maintain. mine has a large loop on both pipes ( hidden by design ) & the lavac valve in the outlet to break the vacuum

 

[[70521]]

Have you considered a Thetford Porta Potti 135 Marine toilet?

 

[johnjfrake]

Thanks for the replies:

I have a source for spares for the SL400 and they can be got. The idea of ball valves is attractive, but given my layout at the front may not be necessary as the seacoks are within easy reach of the loo base. Incidentally the SL400 installation instructions do not show a loop on the inlet side hose just the outlet!

I like the idea of the Lavac and have read nothing but good about them but I have an sl400 in good order and given the money to be spent on lift out, though hulls etc would have to think carefully about adding to the bill for a Lavac.

Yes I am looking at chemical loo options, the main attractions are the simplicity and ability to put it in the cockpit over night, the main disadvantage is the extra height and uncertainty about where you can/cannot empty the cassette. It is by far the lowest cost option.

 

[johnalison]

I had an SL400 for many years on my old Mystere. It was an excellent loo and we never sank, that I can remember. It was long ago and I can't recall whether we closed the seacocks or not.

There is always going to be some risk of siphoning and this varies with each installation. I would suggest fitting the loo without a valve but with a loop in the outlet at least. You will then be able to see if syphoning occurs when static, and if it does, fit a valve, which is not difficult, to whichever pipe is involved.

 

[onesea]

Have you considered a Thetford Porta Potti 135 Marine toilet?

Must admit if I was going to fit a toilet, I would seriously consider similar or
a cassette toilet if it would fit.

Unless I had space for a holding tank...

The rules are coming (within my life time?) so I would call it future proofing...

As for syphon breaks I would certainly put loops of pipe to deck level...

 

[Rossynant]

I've never heard of a yacht sinking due to water siphoning.

Well, there were some; had an experience of sort, real shame to go this way Not siphoning though. Very good advice to have extra valves.
I see no problem without loops and anti-siphon if must be, but when toilet is well above water level and seacocks good, as only risk is some bit of water forced in when at sea. But.

In old rulings antisiphon was mandatory for toilet below waterline.
Boat had no 'loop' on inlet, piping just going down shortest way. And toilet just below water level... This boat made all around Europe and North Atlantic for 30 years, normally no problem even in storm, seacocks were rarely closed as valves in toilet keep water shut. But when inlet (flushing) water started to come in on itself we had to close the seacock and it did not close the flow completely Well, we cleaned the valves in toilet pump (Jabsco, rubber flaps; no spares found aboard of course...) while slowly filling bilges, seacock later replaced.

This can happen with ball valves, as ball runs in plastic which can easily get damaged by any dirt inside when closing. Classic 'plug' bronze type is safer in this respect. And beware of brass junk and such, seen ball valve with no visible ball inside after a season...

I know someone who had a small boat and [...] toilet with no vented loops .
One of his children failed to shut one of the seacocks fully. During the night the toilet flooded and by morning the water level in the cabin had just about reached the level of the bunks.
Fortunately it happened during a club rally so lots of people on hand to help sort things out and get all the wet bedding etc up to a nearby campsite laundry.

http://www.boatus.com/seaworthy/sinking/default.asp

 

[bikedaft]

we have a 40 yr old sl400 whose inlet valve does slowly leak, but the rim of the bowl is 1" above sea level (no anti syphon loop). this reoccurs fairly quickly after replaceing all the innards (twice or 3 x now i think)

so we tend to turn off the inlet seacock when not sitting on the throne

 

[ostell]

SL 400 is an excellent bit of design and I got down to being able to get down to taking out the loo and stripping down the valves etc and back in within 30 minutes. However the first boat had a problem with the inlet seacock and it was a bit disconcerting to see the bowl filling and you couldn't do anything about it. I've also had a maintenance kit supplied where the dimensions were incorrect. Only a mm or so but it meant it wouldn't seal up correctly on assembly.

Current boat came with an SL 400, in fact 2, with a second as a spare in a box. Since the cost of a full maintenance kit for the sl400 (including the diaphragm) was more than the cost of a Jabsco I changed to a Jabsco. Replacement pump assembly is about £60, with maintenance kit at £25.

Both inlet and outlet hoses fitted with antisyphon valves. Can look reasonably neat and tidy if care is taken. I originally had problems fitting the hoses and at the suggestion of a contractor in the yard used Vetus sanitation hose. It made the fitting very easy, well worth the extra cost.

 

[johnjfrake]

Having spent yesterday at boat with friend looking at available space and options have ruled out chemical loo for the moment, its just too high for the space, 8.5 cm doesn't sound like much but its the difference between a comfortable forward lean when seated and a bend if you get my drift. Going to re-assemble the SL400, if it test Ok then bite the bullet for a lift out and quick fit using Marelon combined through hull/seacocks. If it doesn't then looks like forking out for a jabsco compact.

Thanks for all the help!