Water filtration and reverse osmosis. Advice wanted.

[Sandy]

Until quite recently most people drank beer for their daily hydration. May be time to resume.

Warm I hope. Those young chaps who drink almost frozen beer are missing out on taste.

 

[Seven Spades]

I bought a desolator watermaker and I am so glad i did. I think it is the quietist on the market. It is also the easiest to use with just an on and off switch all presures are automatically controlled by software. It also auto-flushes.

 

[geem]

I bought a desolator watermaker and I am so glad i did. I think it is the quietist on the market. It is also the easiest to use with just an on and off switch all presures are automatically controlled by software. It also auto-flushes.

Their are two schools of thought. Fully automatic or fully manual. Fully automatic means lots more to go wrong. Fully manual means a lot less to go wrong. 12v watermakers used to be the way to go but I don't believe that is necessarily the case any more with the increase use of lithium batteries and large solar installations. Our 220v watermaker uses the super reliable Cat 247 high pressure pump. This is powered by a 1.5kw 220v motor. Our 3kw LF inverter can run this motor without issue. Since the only electrics are the motor (no electronics as all) and the only other bits are a needle valve and gauge, there really is little to go wrong with the watermaker itself. You could hafe an inverter failure but we also hafe a diesel genset that functions more as a back up these days than a primary power supply. We can make up to 240 l/hr in warm water such that to make our daily water requirements, we only need to run the watermaker for 15mins per day. If you run for this period every day whilst having breakfast, you don't need to run a flush cycle with this type of watermaker. In addition, running from the inverter uses 500Wh to make our 60 litres per day. This is achievable in a single 150W panel in the Caribbean. Thr other benefit of going the 220v watermaker route, is they are far cheaper. Thr other alternative is you build your own as I did. We have now made 175,000 litres of water since we installed it

 

[Seven Spades]

Ours is 24V and we have lithium, we switch it on when we are motoring. We have a small amount of solar but we can still run the watermaker from it. Inverting from 24V to 240V to operate a motor is a lossy way of making water. We spent a whole summer in the med and only ran the generator for one hour I think we had 6 or seven nights in marinas the rest at anchor.

 

[geem]

Ours is 24V and we have lithium, we switch it on when we are motoring. We have a small amount of solar but we can still run the watermaker from it. Inverting from 24V to 240V to operate a motor is a lossy way of making water. We spent a whole summer in the med and only ran the generator for one hour I think we had 6 or seven nights in marinas the rest at anchor.

We are a 24v. We also have lithium. I am just explaining that there is an alternative to going the energy recovery route in favour of a more robust solution. If you are in far flung places, it's not always easy to get support when things go wrong. The Med is probably easier to support stuff like watermakers than other places.

 

[dgadee]

Their are two schools of thought. Fully automatic or fully manual. Fully automatic means lots more to go wrong. Fully manual means a lot less to go wrong. 12v watermakers used to be the way to go but I don't believe that is necessarily the case any more with the increase use of lithium batteries and large solar installations. Our 220v watermaker uses the super reliable Cat 247 high pressure pump. This is powered by a 1.5kw 220v motor. Our 3kw LF inverter can run this motor without issue. Since the only electrics are the motor (no electronics as all) and the only other bits are a needle valve and gauge, there really is little to go wrong with the watermaker itself. You could hafe an inverter failure but we also hafe a diesel genset that functions more as a back up these days than a primary power supply. We can make up to 240 l/hr in warm water such that to make our daily water requirements, we only need to run the watermaker for 15mins per day. If you run for this period every day whilst having breakfast, you don't need to run a flush cycle with this type of watermaker. In addition, running from the inverter uses 500Wh to make our 60 litres per day. This is achievable in a single 150W panel in the Caribbean. Thr other benefit of going the 220v watermaker route, is they are far cheaper. Thr other alternative is you build your own as I did. We have now made 175,000 litres of water since we installed it

You run 15 mins a day with a 2hp system and we run one hour every two days with a 1hp system. We do the every other day due to the noise. Of course, if motoring any distance we fill up the bow tank, too.

In Greece the water maker has saved us so much hassle. Self built.

 

[geem]

You run 15 mins a day with a 2hp system and we run one hour every two days with a 1hp system. We do the every other day due to the noise. Of course, if motoring any distance we fill up the bow tank, too.

In Greece the water maker has saved us so much hassle. Self built.

How much water do you make per hour?
Our watermaker is installed in the engine room so it's not noisy sat in the cockpit where we have breakfast. The engine room is acoustically lined, which helps a lot and the cockpit floor is 2" thick plus acoustic insulation ( the engine room is under the cockpit floor)

 

[dgadee]

100 or 110l an hour. No room where the engine is. It's a Dehler 37 cruiser/racer rather than a cruiser. One of the rear cabins contains it. Vessels above, gubbins on bulkhead at rear.

It has been going for 6 years now and needs taken apart and remade. Small drips!

I based it originally on a 2kw Honda which was an awful hassle. Even having to keep hatches closed to stop fumes. Now, main engine and inverter.

I used a US pump which was a mistake - had a hard time finding the correct frame motor.

It would be good if there was info for new self build entrants. I knew nothing and made some mistakes. Even John Guest US push fit connectors are made of a different material to European ones, the latter affected by pickle liquid.

 

[geem]

100 or 110l an hour. No room where the engine is. It's a Dehler 37 cruiser/racer rather than a cruiser. One of the rear cabins contains it. Vessels above, gubbins on bulkhead at rear.

It has been going for 6 years now and needs taken apart and remade. Small drips!

I based it originally on a 2kw Honda which was an awful hassle. Even having to keep hatches closed to stop fumes. Now, main engine and inverter.

I used a US pump which was a mistake - had a hard time finding the correct frame motor.

It would be good if there was info for new self build entrants. I knew nothing and made some mistakes. Even John Guest US push fit connectors are made of a different material to European ones, the latter affected by pickle liquid.

What size and how many membranes do you have? I use 3x40" membranes. This is the maximum for the 1.5kW motor. It's a very efficient combination whereby you maximise the output of the Cat pump/motor.
My CAT pump is also a US product using NPT threads. The motor coupling is a CAT product that mates with a standard shaft for a 220v motor sourced in the UK.

 

[dgadee]

Mine is a GP pump. 2 x 40" pressure vessels. Latter were UK but company went during COVID. I had to get a motor from US to fit my pump. Had thought a frame adaptor would be easy to find. Not the case.

What hp tubing do you use? I have food standard inner with SS mesh outer. Wonder if that was needed.

I followed the Cruise RO model.

 

[geem]

Mine is a GP pump. 2 x 40" pressure vessels. Latter were UK but company went during COVID. I had to get a motor from US to fit my pump. Had thought a frame adaptor would be easy to find. Not the case.

What hp tubing do you use? I have food standard inner with SS mesh outer. Wonder if that was needed.

I followed the Cruise RO model.

I use a rubber double reinforced hose. I had the same as you for a while but they did not fair so well. I got a leak from a hose. The new stuff is rated for 3000psi.
As a rule of thumb, each 40" membrane will do 75 litres/hr, so two membranes should do 150l/hr if you have sufficient hp. In the hot Caribbean sea, we get up to 240 l/hr with 3 membranes.
I think the 1hp, Cruise RO model was to work with the Honda generators, which all makes sense. We never went that route as we have always has a 5kVA diesel genset that we used tomrun the watermaker from. We started off with a single 40" membrane and the system organically grew to 3 membranes when I realised it needed to more power to triple the water production if you max out membrane capacity

 

[TSailors]

Take the "remineralization" step with a grain of salt. At home all our drinking water comes from a 6-filter RO system, and we have no ill effects with no remineralization. Besides, if you do have any deficiency, it's easy enough to get some vitamin/mineral supplements for it.

 

[geem]

Take the "remineralization" step with a grain of salt. At home all our drinking water comes from a 6-filter RO system, and we have no ill effects with no remineralization. Besides, if you do have any deficiency, it's easy enough to get some vitamin/mineral supplements for it.

What is the TDs reading after all that filtration?

 

[Beneteau381]

Using RO for washing up and a shower should be ok but is not ok for drinking or cooking with

A lot of my working life, I worked offshore on oil production platforms. All of our water came from RO or desalination plants. We drank it and cooked with it!