Small watermaker 3 gph

[Pizzazz]

Originally Posted by MartinFr

This is the start of the 21" version of this design. The pump is the 105 cam size model. Not sure of final arrangement of components yet.

I like the designs with "all high pressure components in one line with fixed fittings", but for the longer membrane I may opt to put the motor/pump combo upside down in the middle and slightly above the pressure vessel along with a single high pressure hose to the seawater feed port on an elbow fitting. Doing so will allow better protection from water to the motor/pump and possibly better access to remove the membrane for long term pickling and storage.

The only other difference would be the pre-filter. Everything I saw online calls for a 5 micron instead of 20 so I will get a few of both and see how fast the 5 micron will clog up before possibly using a 20 micron.

I will keep this forum posted with final parameters regarding water amount and quality.

Re cost: Pump/motor was under $500 and HTCI vessel/membrane also under $500. I bought all high pressure fittings through Grainger and will try to buy everything else there as well as I think the quality is better then some of the items on Amazon as well as a single source supplier for fittings in case spare parts are needed. I estimate the final version to be slightly below $1,500 but can/could save a substantial amount by using cheaper components. However, I opted for better quality at higher cost that may or may not come in handy down the road.

I hope the attached picture will show up, but that's what I've got so far..

Really looking forward to see what output you get. I have moved back to Europe and can no longer source pumps in the US, sorry everyone. A couple of things to try once you get it running... make sure your fittings are tight, increase the pressure slowly, try different runs at 800 psi, 900 psi, etc. and different voltages, 12.4V, 12.7V, 14.1V (alternator running). The easiest way to measure output is to feed the hoses into bottles, a five gallon for the brine, one gallon for the fresh water and time the output. Do not spend any money on measuring equipent, it does not work well at these small volumes.

Lastly, in the beginning, flush with fresh water after use. Once done, you do not need to flush but do use it often. You can get replacement membranes from Amazon. Also, note that some membranes batches from HCTI are better than others. The first time they sent me an older batch that produced very little output. I explained the flow and they sent me a replacement membrane for free (they discarded the entire batch afterwards).

ex-Pizzazz

[MartinFr]

Thank you for your input! I have now all the low pressure components on its way as well.

Re voltage: I will try to use a 12v regulator (step up/step down) to keep voltage consistent and to avoid rogue pressure changes when starting the engine or sun disappears behind a cloud.

Re flow: I did purchase a rather expensive GPH flow meter (in picture) measuring between 0 and 12 GPH. I will still take your advise on gallon jugs to compare and get absolute results.

I will also tamper a bit with a slow start and slow stop circuit to avoid pressure regulation once an adequate pressure point has been found. The only pressure change (with voltage regulator and slow start/stop) would be pre-filter contamination and water temperature or salinity.

I talked to both HTCI and Pumptec technical support and both are excellent to work with. I almost expect to blow up my first membrane, but will try my best not to, lol.

Again, thanks for all your help and input!

Can't wait for my first glass of fresh water..

[Sonerai1]

Hello Pezzazz, I love your attitude towards simplicity, its my favourite word when it comes to boating, I'm very impressed with your water maker design, however, I'm in Australia and I'm not having much luck getting any response from suppliers in the USA for the PumpTec116c pump, are they rare and hard to find ? Can you recommend a supplier, or Yourself, for the pump and membrane with housing to ship to Australia ? kind regards Terry.

[OldManMirage]

https://www.youtube.com/watch?v=2v-YOk4LPac

[/QUOTE]

Ok, can someone help me on this question ? I just watched the video - which is great, gives you a real idea of noise even if its not a huge concern to me - but in it the guy says the pump is pulling 56 amps. Did I hear that right ? Or did he mean watts ? 56 amps seems like too much. If it correct I guess I can see why it is hard to have power for a watermaker.

[OldManMirage]

Ok, re-reading the original post I think I answered my own question. It IS amps. Not sure why I had a hard time with that. Some days the old grey matter gets sticky and doesn't percolate very well.

[Sonerai1]

Thank you for such a simple no frills water maker design. I've just run mine for the first time and it's awesome ! just one question regarding the temperature of the 12v motor, it seems very hot, I can't hold my hand on it for more than a couple of seconds, apparently this is about 60-70 degrees.C, is this normal ? I can't find any info regarding this on the PumpTec116c Web. sites? regards Terry, on Lake Macquarie in Australia.

[aspindel]

I love your watermaker design and am wondering if you could post a diagram and possibly information on what brand of fittings you used. Setting up a watermaker to run unattended while you are off the boat would require a lot of trust in the high pressure fittings. Thank you.

Most of the units for sale have a 5 micron filter. Can you explain why you went with a 20 micron?

You mention that there is a noise issue. Can you describe how much noise? Do you think I could put the pump and motor in the engine room? There is a _lot_ of room in there being wasted and it is sound dampened. I could maybe "T" into engine raw water in/out for supply/brine.

Thank you so much for your post. I think maybe I can do this.

[pablos_]

My 3gph project. Actualy is about 4gph with 2521 membrane and 1000psi. I am supriced that actually pump is more quiet that expected. I can not hear if it's running when mounted under deck.

[GILow]

Originally Posted by pablos_

My 3gph project. Actualy is about 4gph with 2521 membrane and 1000psi. I am supriced that actually pump is more quiet that expected. I can not hear if it's running when mounted under deck.

Lovely tidy build.[emoji106]

[Captain Bill]

My only concern would be your choice of a 2521 membrane for a nominal three gallon per hour water maker. The flow rate across that large of a membrane is too low and the membrane will probably have a relatively short life. For those who would like to build a similar water maker, I would recommend a 2514 membrane as a more appropriate size. A 2514 is rated at 150 gallons per day, which is closer to Pablos' 100gpd output than his 300 gpd rated 2521. Sadly, a 2514 will cost almost as much as a 2521, but the membranes will last longer, saving money in the long run.

[OneTwoSail]

Very nice build. Good to see someone trying the larger membrane, please keep us updated on its performance. Mind if I ask where you got your pump, and for how much?

[pablos_]

Originally Posted by OneTwoSail

Very nice build. Good to see someone trying the larger membrane, please keep us updated on its performance. Mind if I ask where you got your pump, and for how much?

Ebay, about 600usd

[pablos_]

Originally Posted by Captain Bill

The flow rate across that large of a membrane is too low and the membrane will probably have a relatively short life.

I am not worried about the short life of the membrane. even if it lasts 1-2 years it will be a great result for me. 2514 with vessel was more expensive than 2521.
The most important thing for me is that the pump consumes so little energy that it can run all day using the emergy from the solar panels and even later from the battery. It give me easily >100l water daily which is more than enough. No need to run a loud generator.

[RaymondR]

I'm a bit curious about the flow rate across the membrane shortening the life.

My understanding was that it was the velocity of the sea water side which was important and not the flow rate of filtrate through the membrane which caused problems. It appears that if the membrane diameter was the same the length would not matter much because the velocity of the waste brine would be almost the same.

Enlightenment please.

[ABJ87]

Where are folks order the pump from since Pizzazz is no longer a distributor?