Watermaker Prefilters

[SteveHoiland]

I'm trying to find the right type of 5 micron preprefilters used in Spectra Watermakers so I can purchase them elsewhere The one that came with my new 200T unit had no markings on it at all. I would think it's the same type used by all WM manufactures. I believe it is classified as a "pleated 100% poly cleanable". Am I right on this? Doe's anyone have a favorite manufacture they use?

[Tellie]

Hi Steve, You can use pleated 5-micron filters from other reputable water maker companies in your Spectra. Worth shopping around. I have a question, I see you are in Washington. Is that where you cruise or are you planning on cruising the tropics? The reason I ask is that the 200T is intended for use in the tropics.

[SteveHoiland]

Hi Tellie,
The 200T is designed for areas with open ocean influenced areas for temps of 50 f. and above. In the Pacific N. W. we experience water temperatures of 46f in Seattle, S.E. Alaska in the lower 40's. This area is fed by glaciers in inland waters and reduces the salinety of the feed water. Less saline water reduces pressure on the membrane so we can get away with colder feed temps in this area so I'm told by Spectra techs. But yes I am heading south soon. This was also a concern to me also before I bought the unit. So far I,m pleased with the 200T, instalation was straight forward and Larry at Emarld Hbr Marine was always there when I had a very specific question. Maybe I should ask him for an alternate supplier for the filters. By the way, I was origanly looking at the Little Wonder and by the time I had to purchase the remote gauge panel to get gauges and valves seperated from the membrane housing which Spectra already does it was $50 more side by side.

[CarlF]

I used these without apparent problems but I imagine Spectra doesn't like the practice.

http://www.uswatersystems.com/shop/products/5-Micron-Flow%252dMax-2.75"-x-9.75"-Pleated-Filter-Cartridge-%252d-Flow%252dMax-FM%252d5%252d975.html


They also have the 20 micron size.

Carl

[markpj23]

I found it interesting that Spectra advises that you can easily clean the pre-filter elements by dragging them behind the boat for a while. This could save a lot of expense. Unless of course you try this at 15 knots or something...

[Badsanta]

Get several replacement filters. When one gets dirty replace it with a clean one and then clean the dirty one and let try. If you let them get really clogged they get harder to clean. you will find it easier to clean early and often. depends on the water.

[svbravo]

I have an older HRO System 10. It uses a dual prefilter, w/ a pair of standard 2" filters in parallel for greater flow rate (the System 10 is rated at 26gph). I've developed a crack in the prefilter manifold, which holds the 2 filter housings.
I want to replace the unit w/ off the shelf components, instead of going the "marine" route w/ a factory replacement. I could do this easily w/ two standard 2" housings plumbed in parallel. But this got me thinking about larger filter sizes. It would be nice to just need one filter per change, instead of 2. So a 2 fold question: Is there any reason not to simply go w/ a larger size to get the flow rate up? And if this is feasible, then what is the right size to get the same flow as 2 of the smaller filters. And finally, what is the availability of the larger filters worldwide, as I'll be leaving Mexico next season, and want to get a filter size which is easy to locate.

Thanks for any input

Adam
s/v Bravo

[Therapy]

Originally Posted by Badsanta

Get several replacement filters. When one gets dirty replace it with a clean one and then clean the dirty one and let try. If you let them get really clogged they get harder to clean. you will find it easier to clean early and often. depends on the water.

What about just cleaning the one in there and putting it right back in?

[nonam]

Our spectra watermaker is putting out stinky water for the first gallon or so.Visually,the filters dont look bad but I assume that is the most likely source and that hydrogen sulfide can pass through the membrane and get to the tank?And ,in fact,the stink could even come from the 50 micron pre filter?So just washing the filters cannot get all of the stinky bugs out.You reduce the population,but they recover faster?Drying the filters will kill the bugs but is there any risk of dead bugs clogging the membrane?Do bugs populate the membrane?Does the membrane need to be treated with biocide when you get stinky water?Our membrane is only 3 months old.

[Tellie]

Originally Posted by nonam

Our spectra watermaker is putting out stinky water for the first gallon or so.Visually,the filters dont look bad but I assume that is the most likely source and that hydrogen sulfide can pass through the membrane and get to the tank?And ,in fact,the stink could even come from the 50 micron pre filter?So just washing the filters cannot get all of the stinky bugs out.You reduce the population,but they recover faster?Drying the filters will kill the bugs but is there any risk of dead bugs clogging the membrane?Do bugs populate the membrane?Does the membrane need to be treated with biocide when you get stinky water?Our membrane is only 3 months old.

What model of Spectra do you have?
What area are you sailing in?
Hydrogen sulfide gas can pass through the membrane.
The dead "bugs" will not pass through the membrane. What happens is if the dead bus are left in the watermaker the decaying process is what clogs membranes. Membranes are permeable by many gasses including Hydrogen sulfide, the gas that makes the rotten egg smell. Usually the source is from the decay of planktonic creatures trapped in the raw water strainer and the pre-filters. These creatures need oxygen., Once the oxygen is consumed anaerobic bacteria begins to grow causing the rotten egg smell. If a watermaker that is used frequently begins to make smelly water it will be the pre-filters that are the problem. This can occur in two weeks in colder climates and less than two days in very warm waters with high growth. These creatures can clog a membrane and cause the pressures to rise on the system and reduce product rate and flow.Once bacteria begins to colonize on the membrane it is difficult or impossible to eradicate. But if the unit is making smelly water but not salty water open the pressure relief valve 3/4 turn and let the system run for an hour or two to give the membranes surface a good flush first before trying to chemically clean the system.

[Bartoon]

I have just purchased a Spectra Catalina 300 Mk2. After only 12 hours of use, I get a ''Service Prefilter'' warning and the unit stops. The series of 5 blocks showing the status of the filter (5 full equals no good) is showing 3 full and 2 empty i.e. filter should be ok. In the manual, it says I should have received a ''Low Flow'' warning first. I did not. The agent tells me it's because of the poor water quality where I live (Hong Kong), but I find it hard to believe that a filter can clog so quickly, and why not Low Flow?
The Catalina is peculiar in that it has only a 5 micron filter -- no 20 micron first. There is a crude strainer, of course.
Does anyone have any experience of this? I plan to fit a 20 filter immediately before the 5, but I suspect there may be something else wrong. All comments welcome!

[Capn Morgan]

According to the agent we bought our 200T from, any pleated cellulose 5 micron filter will do. I keep one unused spare and swap two used ones every few days. I clean the one taken out with sea water and let it dry. The manual recommends doing this every day (!). Never a problem in 2 years and I use it even in the marina, which admitedly is not too dirty. May I ask what sort of ppm readings you get from yours?

[Tellie]

Originally Posted by Bartoon

I have just purchased a Spectra Catalina 300 Mk2. After only 12 hours of use, I get a ''Service Prefilter'' warning and the unit stops. The series of 5 blocks showing the status of the filter (5 full equals no good) is showing 3 full and 2 empty i.e. filter should be ok. In the manual, it says I should have received a ''Low Flow'' warning first. I did not. The agent tells me it's because of the poor water quality where I live (Hong Kong), but I find it hard to believe that a filter can clog so quickly, and why not Low Flow?
The Catalina is peculiar in that it has only a 5 micron filter -- no 20 micron first. There is a crude strainer, of course.
Does anyone have any experience of this? I plan to fit a 20 filter immediately before the 5, but I suspect there may be something else wrong. All comments welcome!

I know a couple of things about Spectras.
Fitting a 20 Micron before your 5 Micron is going to give you even more fits with your bar scale and control system.
First question. Did you have a Spectra factory trained tech install your watermaker or did someone else? I'm not trying to be snide but this is important because I have seen plenty of unintentional bad installs.
But here's a few things to check first.
1) How high is the feed pump head mounted in relation to your boats waterline?
2) How far is the thru-hull intake from the feed pump module?
3) Is there a dedicated thru-hull just for the watermaker and how big is it?
4) Is there a boost pump installed after the raw water strainer and before the feed pump module and is it below the waterline?

Where in Hong Kong are you running your watermaker? Is the water dirty? Your agent may be right. Watermakers are not intended for dirty water. It's very possible to clog the 5 Micron filter in 12 hours in less than ideal water. I've seen them clog even faster on the ICW. If the filter is really dirty then the MPC control is doing exactly what t should be doing in shutting your system down. It may not seem like it now, but that's good.
It's possible, but not likely, with only three bars darkened that the programing is off. There is a feed water pressure sensor and an absolute pressure sensor that may need to be re-set. A simple task with a lap top but I'd suggest you leave that to a qualified Spectra tech and not attempt any programming from the control panel without someone who is trained and knows what they are doing helping you step by step. These settings are set at the factory and tested. It's rare that they are off but things do happen in the real world.
Also very important is the voltage readings at the terminal strip that feeds the watermaker. Your Catalina is voltage sensitive and if it was not installed with the proper sized wire and electrical procedures it could give erratic readings. Check the voltage at the terminal strip with the system running.
Even reading three bars on the scale indicates low flow or blockage somewhere. The Catalina300 is one of the best units made and I'm betting your problem is very minor. Check these few things out first and get back top me if you are still having a problem.

[Bartoon]

Originally Posted by Capn Morgan

According to the agent we bought our 200T from, any pleated cellulose 5 micron filter will do. I keep one unused spare and swap two used ones every few days. I clean the one taken out with sea water and let it dry. The manual recommends doing this every day (!). Never a problem in 2 years and I use it even in the marina, which admitedly is not too dirty. May I ask what sort of ppm readings you get from yours?

Thanks Capn M. Ppm is about 200. Having now changed the filter, the culprit seems to be fine silt washed down from the Pearl River. Oh well, life was never simple!

[Bartoon]

Originally Posted by Tellie

I know a couple of things about Spectras.
Fitting a 20 Micron before your 5 Micron is going to give you even more fits with your bar scale and control system.
First question. Did you have a Spectra factory trained tech install your watermaker or did someone else? I'm not trying to be snide but this is important because I have seen plenty of unintentional bad installs.
But here's a few things to check first.
1) How high is the feed pump head mounted in relation to your boats waterline?
2) How far is the thru-hull intake from the feed pump module?
3) Is there a dedicated thru-hull just for the watermaker and how big is it?
4) Is there a boost pump installed after the raw water strainer and before the feed pump module and is it below the waterline?

Where in Hong Kong are you running your watermaker? Is the water dirty? Your agent may be right. Watermakers are not intended for dirty water. It's very possible to clog the 5 Micron filter in 12 hours in less than ideal water. I've seen them clog even faster on the ICW. If the filter is really dirty then the MPC control is doing exactly what t should be doing in shutting your system down. It may not seem like it now, but that's good.
It's possible, but not likely, with only three bars darkened that the programing is off. There is a feed water pressure sensor and an absolute pressure sensor that may need to be re-set. A simple task with a lap top but I'd suggest you leave that to a qualified Spectra tech and not attempt any programming from the control panel without someone who is trained and knows what they are doing helping you step by step. These settings are set at the factory and tested. It's rare that they are off but things do happen in the real world.
Also very important is the voltage readings at the terminal strip that feeds the watermaker. Your Catalina is voltage sensitive and if it was not installed with the proper sized wire and electrical procedures it could give erratic readings. Check the voltage at the terminal strip with the system running.
Even reading three bars on the scale indicates low flow or blockage somewhere. The Catalina300 is one of the best units made and I'm betting your problem is very minor. Check these few things out first and get back top me if you are still having a problem.

Many thanks, Tellie.
1. About a foot below.
2. About 8 feet.
3. Yes, 3/4"
4. Yes and yes.

The 5 micron filter was totally black -- looks like Pear River Delta silt. Spectra have okayed a 20 micron filter so I'll try that, but it looks like I'll be limited to using the watermaker only when I go sailing. Good job I have shore water!