Watermaker info resources UK

[lustyd]

Hi all, does anyone have any good watermaker resources in the UK? Shops, docs, etc.

Debating making our own and would be useful to have info on stuff that's available locally to properly compare to prebuilt stuff.
Thanks
Dave

 

[Neeves]

Rainman in Australia build desalinators from off the shelf components (and a few custom items, pipe joints etc.). Their original unit was based on a Honda petrol engine - but they have branched out.

Theirs is a desalinator in a brief case - sounds like a good idea, fits in with a power station in a box.

I have not looked but you may find they define who their suppliers are (as customers might want assurance of quality).

Looking at their website may give you some ideas - even if nothing else

Rainman are based locally to me and I like their ideas. I tested out the original unit - simple, clever stuff. I note you are, I deduce, looking for UK sources. I've not enquired (being truly multicultural the many of us are immigrants) but one of the founder members has an American accent (maybe means nothing) but this may be reflected in some sourcing. Another founding member 'sounds' Australian, lived (still lives?) on his yacht and the first unit was part designed to meet his demands. If Rainman had been around we would have bought one of their units in preference to Spectra.

Jonathan

 

[lustyd]

I have seen Rainman but really looking for built in watermaker

 

[Neeves]

I have seen Rainman but really looking for built in watermaker

I'm not sure what a 'built in watermaker' means.

Our Spectra came as 2 pumps, a membrane, a Clark pump a lot of pipework, some valves, a raw water filter and a cartridge filter.

Because it came as individual units we could tuck the various pieces into locations which otherwise were wasted spaces but locate the items needing service, primarily the cartridge filter, in locations that were easily accessible. The membrane we never needed to touch and was tucked up in the corner between and under the cabin sole and parallel to the side of the hull.

If the watermaker comes as a small suitcase - you have need to have suitcase sized empty spaces (which are actually available on a cat but seem like dragons teeth on a yacht).

Jonathan

 

[lustyd]

I'm not sure what a 'built in watermaker' means.

The Rainman is probably a good example of the opposite of built in, it's designed to be portable rather than plumbed in permanently. In theory one could disassemble it or just bolt it in place, but there are better and cheaper options for permanent install. We may yet end up with a Rainman as the boat is only 36' and install locations all detract from storage space, but I'd much prefer something installed with a control panel somewhere convenient but with the gubbins hidden away somewhere.

 

[AntarcticPilot]

Just to widen the discussion, reverse osmosis water filters are a common thing in Hong Kong; people here generally don't trust tap water! A countertop one costs around £500; a Google search will bring up LOTS of hits. Of course, they need mains voltage. They seem to have a fairly high throughput; the one in the apartment where I am right now provides water on demand. I have no idea whether they would be OK with seawater! It produces about 1 litre of water for ABOUT 4 litres waste.

 

[ashtead]

Dave, Should you be based on the south coast I recall there is a supplier of water makers in south which you can self install. I know that a DS 41 which was on our pontoon installed one below the cabin sole before they set off onARC (they are still sailing around that area as they post occasionally - am guessing as a while ago but I see sailfish marine near Southampton sell water makers -others might have used them and know more.

 

[Neeves]

The Rainman is probably a good example of the opposite of built in, it's designed to be portable rather than plumbed in permanently. In theory one could disassemble it or just bolt it in place, but there are better and cheaper options for permanent install. We may yet end up with a Rainman as the boat is only 36' and install locations all detract from storage space, but I'd much prefer something installed with a control panel somewhere convenient but with the gubbins hidden away somewhere.

I don't have a picture - never though it would be interesting as it seemed simple

I took the Spectra flow or plumbing chart and transferred it to marine ply. I simply drilled the ply to accept the various valves installed the valves and then the pipe work at the back. The completed panel was about 500mm x 250mm. and fitted inside the door of a cupboard ( the panel was sized to fit the cupboard) and all the pipe work to the membrane (which fitted above) and the 2 pumps and filters (immediately in front but under the cabin sole) and the Clark pump about 1500mm away were hidden away. We labelled all the valves and anyone could operate the controls simply by reading the Spectra instructions.

Our panel 'used' the bottom shelf of a cupboard, open the door and under the shelf flush to the door when closed were all the valves and much of the pipe work was behind (except for the pipe work for the pumps etc which disappeared under the cabin sole)

Jonathan

A word of caution. The filter housing for the main filter can be a tight fit and I used the sort of device you use to remove an oil filter (or a tight jam jar lid) but filter sized. You need room to wield such a device or room to get your hands round the filter housing and twist the recalcitrant unit - so leave some room. The raw water filter was a simply one handed 'service' and nothing else ever went wrong. We never had any leaks.

We had 2 water tanks and would use one tank till empty, then the other. We could fill each tank with extra valves we bought and kept the 2 tanks independent of each other. We never used water other than water from the desalinator. If the engine went on, to enter an anchorage, the desal unit would have been started 30 minutes prior to make use of the amps. We always ran the engine(s) when anchoring (as the windlass is a big consumer) or retrieving and the engine(s) and desal always 'worked' together.

 

[Neeves]

Just to widen the discussion, reverse osmosis water filters are a common thing in Hong Kong; people here generally don't trust tap water! A countertop one costs around £500; a Google search will bring up LOTS of hits. Of course, they need mains voltage. They seem to have a fairly high throughput; the one in the apartment where I am right now provides water on demand. I have no idea whether they would be OK with seawater! It produces about 1 litre of water for ABOUT 4 litres waste.

If the water is 'fresh' the throughput is higher. If you are desalinating water near a river entrance or on a tidal river you get much higher throughputs than from sea (salt) water. I suspect the units in HK are designed to remove different 'things' rather than, only, salt,

We lived at Discovery Bay in its early stages of development and the water came from the reservoir up on the hill behind the development - we never thought twice about the fresh water . Fresh water was freely available. When we moved there the population was 1,000 - how times change.

Jonathan

 

[geem]

Just to widen the discussion, reverse osmosis water filters are a common thing in Hong Kong; people here generally don't trust tap water! A countertop one costs around £500; a Google search will bring up LOTS of hits. Of course, they need mains voltage. They seem to have a fairly high throughput; the one in the apartment where I am right now provides water on demand. I have no idea whether they would be OK with seawater! It produces about 1 litre of water for ABOUT 4 litres waste.

They are totally different to seawater RO systems. They are low pressure RO system to clean up fresh water. Not suitable for boats. Seawater RO systems run at 800psi. A far higher membrane pressure.

 

[AntarcticPilot]

If the water is 'fresh' the throughput is higher. If you are desalinating water near a river entrance or on a tidal river you get much higher throughputs than from sea (salt) water. I suspect the units in HK are designed to remove different 'things' rather than, only, salt,

We lived at Discovery Bay in its early stages of development and the water came from the reservoir up on the hill behind the development - we never thought twice about the fresh water . Fresh water was freely available. When we moved there the population was 1,000 - how times change.

Jonathan

I think Discovery Bay might have changed just a little!

 

[AntarcticPilot]

They are totally different to seawater RO systems. They are low pressure RO system to clean up fresh water. Not suitable for boats. Seawater RO systems run at 800psi. A far higher membrane pressure.

Thanks - I'm not up on the technical side. I understand the principle but haven't investigated the details. Of course, because the osmotic pressure to be overcome is much less, that all makes sense.

 

[geem]

Hi all, does anyone have any good watermaker resources in the UK? Shops, docs, etc.

Debating making our own and would be useful to have info on stuff that's available locally to properly compare to prebuilt stuff.
Thanks
Dave

There is not a lot in the way of RO resources in the UK.
Are you thinking of a 12v system or a 220v system?
A energy reclaim 12v system is complex and probably better bought off the shelf. You can build a 12v or 220v simple system using a pair of pre-filters, centrifugal boost pump, HP pump, needle valve, pressure gauge and diverted valve. Not much more to it than that.
I built mine in 2013 and it has made 50 or 60 litres per day for just about every day we have been aboard since 2014.
I used a second hand Cat 247 pump mated to a 1.5kw 220v motor. The boost pump is a Stuart Turner brass 220v centrifugal pump. The HP membranes are 40" units rated at 700US gpd. We have 3 installed. All other bits are sourced from the Internet. The system is super simple and robust.
The cat pump will absorb the same amount of power regardless of the number of membranes plumbed in series. We max out the flowrate of the cat pump such that litres per Watt of power used is as efficient as possible. The unit produces 200 litres per hour so 15 to 20 mins run time per day is all we need. The power to do that is about 600Wh.
We can run the watermaker from the diesel genset or the 3kw inverter.

 

[lustyd]

Dave, Should you be based on the south coast I recall there is a supplier of water makers in south which you can self install. I know that a DS 41 which was on our pontoon installed one below the cabin sole before they set off onARC (they are still sailing around that area as they post occasionally - am guessing as a while ago but I see sailfish marine near Southampton sell water makers -others might have used them and know more.

Thanks yes I'd seen Sailfish but hard to know where to start other than buying one of the full machines. Under the sole might be a good idea, I'll measure up.
Yes, we're at Haslar on F pontoon

 

[lustyd]

You can build a 12v or 220v simple system using a pair of pre-filters, centrifugal boost pump, HP pump, needle valve, pressure gauge and diverted valve. Not much more to it than that.

Yes that bit I've understood, was hoping for some simple guidance as to which pumps etc. and what the things to look out for are, and more importantly where to get the bits in the UK as well as making sure I only buy stuff that's also available relatively easily globally. Most of the resources for this kind of thing are US centric, much like with sewing all paths lead to Sailrite!

 

[geem]

Things like HP pipes can be sought from Hydraulic megastore on line.
You need to work out how much power you are prepared to sacrifice to run the system and how much water you need to make. Once you have that info, you can decide what pump you can run at what power. Cat have some good pumps and tables for sizing the motor. There are cat pump agents in the UK.
The cylinder head needs to be bronze or 316 S/S.

 

[Dunx]

Have you seen this group on FB?

https://m.facebook.com/groups/203626974514769/?ref=share

 

[lustyd]

Have you seen this group on FB?

https://m.facebook.com/groups/203626974514769/?ref=share

For some reason I didn't even think to look, thanks very much!

 

[Tradewinds]

I've used theses people for a replacement membrane.

https://www.desal.co.uk

 

[lustyd]

I've used theses people for a replacement membrane.

https://www.desal.co.uk

Thanks this looks like a much better (organisation wise) website than the others