markc
Well-Known Member
This is a good idea. Perhaps it could be fitted to the shore to boat supply hose making it simple to install and simple to bypass if necessary?
Any idea what this is?
- Thread starter markc
- Start date
petem
Well-Known Member
Interesting ideas but surely you need a time frame to measure the volume of water against to sense a leak?
Another alternative would be an electronic valve that shuts off the shore power water feed whenever a bulge pump switch or bilge alarm is triggered.
Another alternative would be an electronic valve that shuts off the shore power water feed whenever a bulge pump switch or bilge alarm is triggered.
jrudge
Well-Known Member
No. They reset each time the water stops. So any continuous use of 50 l stops the water. 49l and off it just resets
maby
Well-Known Member
Our previous boat had "shore water" and we were never able to use it. Every marina we visited refused to allow it to be connected - H&S issues apparently related to rules designed to protect the mains water supply from contamination. They all told me that we would need quite a sophisticated control system between the boat and the mains supply before they would permit the hookup. We were parked up next to a superyacht for a while which was was hooked up to shore water and they had a device with two large clear cylinders installed in the hose - I assume that was the sort of thing the marinas were talking about.
Portofino
Well-Known Member
That’s the real reason of the one way valve ( irrelevant exactly where relative to anything in the boat ) near the “IN “
It’s a crude attempt to restrict back flow out of the boat .
Unusual pressure reversal situation.
You need a type 1 air gap really to isolate boat from mains .
Those transparent cylinders are just plane vanilla bog ( scuse the pun ) standard water filters , allegedly to remove calcium carbonate, and other hardners sos when tgey wash the SY in the sun it’s doesn’t leave calcium rings when it drying.
Bigger boats / SY have permanent crew and more space for water management kit , and alarms and sensors etc
You are better off using your tank and just keeping a high turn over in there at the dock and dropping any proprietary water treatment ( antibug ) tab in as instructed.
Making sure now and Agian you run any dead ends ,- like taps in an unused for ages ensuite .
Legionella is the bug that thrives at 37 degrees in stale dead ( scuse the pun again ) ends .Spead by airborne droplets - showers / slashing etc ,- plenty of that on the bathing platform in the Med .Risky - you decide ?when compared with water use at home .
Try and open both ends of your hoses when coiling up etc to allow water to run out - stuff like that .Before it’s chucked in a locker for the contents to ferment .
I would not want a fixed conected hose from the dock in the Med sun connected to my boat for the inherent potential health issues - more so if little kids on board .
Thinking diarrhoea.
Not we are on toilets
Again there’s no cystern , type 2 ( sorry memory fades ? ) air gap .
So think about it there’s an increased possibility of contamination from the bowl to the tank , or in this case the bowl to the jetty mains .
Reflect a mo on that thought - a few boats contaminated water now connected up - perhaps one or two have relatively unsophisticated bogs - not a good as say a Tecma ?
That’s why marina s - sensible ones that have done a proper risk assessment get uperty with dock side permanent connections .
MapishM,s gonna tell me again that he and all aboard have in 35 years (?) suffered zero ill effects with permanent dock water connection.
I,ll tell you that the oldest living European lived to 110 ish and smoked every day - go figure .
One of one is not enough in diesease pattern epidemiology.
It’s a crude attempt to restrict back flow out of the boat .
Unusual pressure reversal situation.
You need a type 1 air gap really to isolate boat from mains .
Those transparent cylinders are just plane vanilla bog ( scuse the pun ) standard water filters , allegedly to remove calcium carbonate, and other hardners sos when tgey wash the SY in the sun it’s doesn’t leave calcium rings when it drying.
Bigger boats / SY have permanent crew and more space for water management kit , and alarms and sensors etc
You are better off using your tank and just keeping a high turn over in there at the dock and dropping any proprietary water treatment ( antibug ) tab in as instructed.
Making sure now and Agian you run any dead ends ,- like taps in an unused for ages ensuite .
Legionella is the bug that thrives at 37 degrees in stale dead ( scuse the pun again ) ends .Spead by airborne droplets - showers / slashing etc ,- plenty of that on the bathing platform in the Med .Risky - you decide ?when compared with water use at home .
Try and open both ends of your hoses when coiling up etc to allow water to run out - stuff like that .Before it’s chucked in a locker for the contents to ferment .
I would not want a fixed conected hose from the dock in the Med sun connected to my boat for the inherent potential health issues - more so if little kids on board .
Thinking diarrhoea.
Not we are on toilets
Again there’s no cystern , type 2 ( sorry memory fades ? ) air gap .
So think about it there’s an increased possibility of contamination from the bowl to the tank , or in this case the bowl to the jetty mains .
Reflect a mo on that thought - a few boats contaminated water now connected up - perhaps one or two have relatively unsophisticated bogs - not a good as say a Tecma ?
That’s why marina s - sensible ones that have done a proper risk assessment get uperty with dock side permanent connections .
MapishM,s gonna tell me again that he and all aboard have in 35 years (?) suffered zero ill effects with permanent dock water connection.
I,ll tell you that the oldest living European lived to 110 ish and smoked every day - go figure .
One of one is not enough in diesease pattern epidemiology.
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petem
Well-Known Member
Ah, that makes sense, happy days then.
MapisM
Well-Known Member
Waddumean unusual?
Once you turn on the onboard domestic fresh water pump, the pressure inside the dockside line is obviously reversed.
Without a one way valve, your tank reserve would be flushed back out from the dockside connection as soon as you detach the dock hose.
THIS is the real (and simple) reason for the valve, with no presumption at all to sterilize the boat or whatever!
Now you tell me... I'll start smoking asap. Better late than never, I reckon! :encouragement:
MapisM
Well-Known Member
I'd rather assume that they just didn't want to argue with a superyacht client, 'cause PF is correct when he says that those cylinders more than likely were just filters, which are pretty useless in stopping contamination, if any.
Regardless, in which area are located the marinas you are talking about? In the Med, I've yet to find one which raised any objection.
maby
Well-Known Member
I'm talking about southern England - particularly the Solent area. I have asked at several marinas along the south coast and always received the same answer - H&S rules do not permit the connection of the boat water system to the mains water supply without the inclusion of filters capable of blocking micro-organisms. I even offered to pay for a dedicated connection to be installed on the pontoon at our permanent berth in Ocean Village and was told that it was not possible under the rules in force.
MapisM
Well-Known Member
Aha, I see. I still very much doubt that any mechanical filter can block bacterias, but hey-ho!
Portofino
Well-Known Member
Run all this by Agian ps .
I thought a proper factory built or reputable yard ie none badger DIY er , would install the dock water connection to work along these lines
By pass the tank and pump — so,s via the PRV ( set accordingly of course ) you just turn a tap or what ever and water flows direct straight from the jetty , via the sun drenched hose
Prob in my mind of connecting up the tank is it will pressurise when all the outlets like taps etc are off .Tank + ancillaries is meant to be pressure passive —— pump sucks out water and sends it where asked by the user .
So imagine the seals around various connections / orrifaces , like the sender for eg , or explain please how the air vent dirs not spurt out ? .
1/ 2 decent accumulators too after the pump or the pump itself I think won,t like - 4 bar or what ever mains water pushing constantly either I reckon .
Happy to hear how you think it could work .
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maby
Well-Known Member
Aha, I see. I still very much doubt that any mechanical filter can block bacterias, but hey-ho!
There are micro-filtration systems that will remove bacteria, but they are expensive.
MapisM
Well-Known Member
I'm not sure to have understood exactly what your doubt is, but I can't see how you could have a separate circuit for the dockside connection, bypassing the tank and pump.Run all this by Agian ps .
I thought a proper factory built or reputable yard ie none badger DIY er , would install the dock water connection to work along these lines
By pass the tank and pump — so,s via the PRV ( set accordingly of course ) you just turn a tap or what ever and water flows direct straight from the jetty , via the sun drenched hose
Prob in my mind of connecting up the tank is it will pressurise when all the outlets like taps etc are off .Tank + ancillaries is meant to be pressure passive —— pump sucks out water and sends it where asked by the user .
So imagine the seals around various connections / orrifaces , like the sender for eg , or explain please how the air vent dirs not spurt out ? .
1/ 2 decent accumulators too after the pump or the pump itself I think won,t like - 4 bar or what ever mains water pushing constantly either I reckon .
Happy to hear how you think it could work .
I mean, you would need two completely separate circuits for everything, up to having a double set of taps everywhere, and even double toilets...?!?
In practice, the way dockside connections work (also in boats where it's factory installed) is as follows:
The internal circuit is business as usual - the pump sucks from the tank and pressurizes the whole circuit.
Regardless of whether it has an expansion tank or not, the pump has its own one way valve, so upstream of the pump the tank is actually "disconnected", sort of.
The dockside connection attaches anywhere along the internal circuit, with its own one way valve.
So, whenever you don't have an external hose attached, this valve keeps the internal circuit closed (and pressurized by the pump).
When you attach the external hose, the pressure from the dock line keeps the whole internal circuit pressurized as it would be with the pump, but without needing to run it.
This means that normally you can't refill the internal tank directly from the dockside connection.
In fact, jrudge said in his post #16 that he could, but only because he fitted another valve (I suppose a manual valve on a T connection, which when opened allows the dockside flow to be routed also inside the tank).
Fwiw, I've never seen that in any OEM installation, and I didn't bother doing that when I modified my previous boat.
A nice to have feature it is, though.
jrudge
Well-Known Member
A confession.
Mine was on my T40. The pump was under the rear berth bed. It took probably 10 mins and £10 to add in the valve whilst i was working there , but as i recall i never used it even once! Putting the hose in the tank was simpler than lifting the berth.
Now i have 1000 litre tanks ( T40 was 300) if in the marina over winter for example a tank lasts maybe 7 days so I am not sure I would bother with shore supply again. Also the hose connections always used to leak!
MapisM
Well-Known Member
Far from pretending to be an expert on this matter, but my understanding is that (aside from boiling water), only a full flagged reversal osmosis purifier can give a good degree of safety.
And aside from cost, it's also quite a bit of kit to install and deal with...
MapisM
Well-Known Member
LOL, there speaks a man who knows what real life problems are.
How hard can it be to design a bloody garden hose connector which doesn't leak, I always wondered...
jrudge
Well-Known Member
I did buy a load of brass ones.
I dont recall them being any better.
It is usually the join to the shore tap that leaks in some way or another and it always seems to fall into the "why should i sort out their issue" bucket. The taps themselves also seem to leak. The marina of course does not care as most of them are metered connections so you get the bill!
I dont recall them being any better.
It is usually the join to the shore tap that leaks in some way or another and it always seems to fall into the "why should i sort out their issue" bucket. The taps themselves also seem to leak. The marina of course does not care as most of them are metered connections so you get the bill!
