Spectra Watermaker Filter Cleaning?

[Kenomac]

Originally Posted by VeinDocFL

I had not tried drying them out after cleaning. Also had not really paid attention to the number being displayed on the prefilter menu item. I take it that is resistance pressure. Don't really recall seeing that in the manual but will go back and look and monitor that number with time. Running new filters today in eastern Long Island Sound and after four hours it shows 18.52 on it. Didn't look before I started though. Saved the last filters so sun drying as we speak. Thanks for the input. I would be happy to just use new filters but with living on the boat for six months I was hoping not to haul too many items and arranging a drop ship somewhere is a bit of a hassle.
That kind of filters did you buy in bulk and from who?

I purchased the Spectra filters from a Spectra dealer by the dozen and got the price down below $10 each. But now with cleaning and drying them out for a couple of days, the filters are lasting 4 times as long. Make sure you dry the filters in the sun until they’re bleached white.

[Tellie]

Finally back from from a long stay away. It's good to get back to CF.
A few things, Pre-filters are the consumable parts of any watermaker. A good quality polyester filter should be able to be re-used two or three times if it is changed out in a timely manner. If you leave it in your system for months on end then it is unlikely a cleaning will do much. Usually you will change out your filters every 30-45 days if you are using your system regularly. Cleaning a filter should only be done by using a steady stream of water with about as much pressure that would come out of a shower head. You "NEVER" scrub or brush filters unless you want to make a 5 Micron pre-filter into a 500Micron pre-filter. Bleaching does no more than make a filter a bit whiter, anything embedded into the filter will still be there for the most part just a bit whiter. I used to recommend dragging filters behind a boat as well back in the day. But this is a very bad practice. The common way to do this was to run a line through the middle of the filter and tie a safety knot at the end of the line and toss the filter over board to be dragged along. The problem with this is that you actually reverse the direction of flow as the water is forced through the middle of the filter effectively filtering the salt water from the inside out in the opposite direction of the normal flow through the filter. The filter does what a filter does and collect particles smaller than the rated micron on the inside of the filter. Now when you re-use the filter the flow now is reversed and all the particulates picked up go straight to the membrane and start to clog the membrane. Years ago I recommended this to a customer and the results were disastrous. He called me from the middle of the Atlantic saying his membrane was no longer working on a brand new unit. After several months and three membrane change outs we finally figured out the issue. He had dragged the filter behind as "I" suggested. A small flying fish got caught in the inside of the filter and emulsified. Every timer he used this filter the emulsification clogged the membrane. After a thorough cleaning of the entire system if worked great for years. But the customers frustration was certainly understandable. Shipping three membrane to Figi, New Zealand, and then Australia hit my wallet pretty hard. If your filters stink each time you remove them then your system is not fresh water flushing properly and this should be addressed to correct the problem. I've never sailed in the Chesapeake but I can tell you this, I have more problem calls from that body of water than almost any where else in the world. As I always say, watermakers are off shore equipment where the water is nice and clean, the Carib and most places with Islands are usually just fine. Running them in the ICW and such places is usually a recipe for disaster. Pre-filters are cheap enough as one poster stated. What you pay for any watermaker does not justify being cheap. If you got a cheap watermaker then buy cheap filters. Also, to leave you with my old adage "When in doubt, change them out"

[a64pilot]

I learned pretty quickly to clean the 20 micron once, but never clean the 5 micron.
My line of reasoning is that if by cleaning the 20 it becomes say a 50, no harm the 5 will catch it, however if you mess up the 5, then whatever gets through goes to the membrane.

On mine it’s the 20 that usually clogs first anyway, so I’ll take it out clean it and we go back into production, next time water pressure begins to drop, I replace both.

Filters can be bought that are paper or polyester, avoid the paper ones.
The paper ones won’t specify what they are made from, often the polyester ones will. So spend a little more on a Polyester filter.

[accomplice]

I am a new owner of a Catalina 340, which replaced a SeaRecovery 900gpd. I am shocked at how quickly the Catalina goes through filters, even when using a pre-filter ahead of it. We only get 200-300 gallons of product out of each filter, compared to thousands of gallons for the SeaRecovery filters.

I suspect that the difference has not only to do with the smaller surface area of the filter, but also with the much weaker booster pump. I'm not sure what the spectra is using for a booster pump, but I know it is less powerful than the 3/4hp unit on the SeaRecovery. I understand they want good power efficiency numbers, but I suspect this is part of the price paid.

I have transitioned to bulk/generic filters. I am considering fitting an alternate pre-filter and also considering adding a more powerful booster pump.

How many gallons of product do you get from your filters?

[Tellie]

Originally Posted by a64pilot

Filters can be bought that are paper or polyester, avoid the paper ones.
The paper ones won’t specify what they are made from, often the polyester ones will. So spend a little more on a Polyester filter.

[Tellie]

Originally Posted by accomplice

I am a new owner of a Catalina 340, which replaced a SeaRecovery 900gpd. I am shocked at how quickly the Catalina goes through filters, even when using a pre-filter ahead of it. We only get 200-300 gallons of product out of each filter, compared to thousands of gallons for the SeaRecovery filters.

I suspect that the difference has not only to do with the smaller surface area of the filter, but also with the much weaker booster pump. I'm not sure what the spectra is using for a booster pump, but I know it is less powerful than the 3/4hp unit on the SeaRecovery. I understand they want good power efficiency numbers, but I suspect this is part of the price paid.

I have transitioned to bulk/generic filters. I am considering fitting an alternate pre-filter and also considering adding a more powerful booster pump.

How many gallons of product do you get from your filters?

Hold tight there.
a) DO NOT add a larger boost pump. You will send the electronics into all kinds of chaos. Not that many years ago none of the watermakers in Spectras line had a boost pump at all and those systems ran for years just fine. The sole purpose for the boost pump is to feed a small amount of head pressure to the feed pump so it doesn't have to draw water from the thru hull up to the feed pump itself. This helps the feed pump to last longer and avoid air cavitation. Also, the fresh water flush on your system is designed to start at the raw water strainer and boost pump module.

2) You don't need to add more filtration. Again, years ago we used a 50 micron pre-filter, a 20 Micron pre-filter and a 5 Micron pre-filter on the Catalina models. After years of experience we've learned that a 5 Micron is all you need on the Catalina system. The newer 340's like yours move even more water than the older 300's.

3) Filter life is not based on either time or volume of water passed through the filter. The condition of the water you are floating in is the prime determination of filter life. If you are changing your filters out more often than 30-45 days of regular use then the problem may be more of making sure your sensors are set right.

For those with an older Catalina300 with mag drive pumps, when it's time to replace the feed pump head let me know. We will replace the older 110psi pump with a newer 140psi pump head used on the newer 340's and this will increase your output about two to three more gallons and it's the same mounting as the 110psi so no modifications are needed. Just four easy screws and your done.

[accomplice]

Originally Posted by Tellie

Hold tight there.

3) Filter life is not based on either time or volume of water passed through the filter. The condition of the water you are floating in is the prime determination of filter life. If you are changing your filters out more often than 30-45 days of regular use then the problem may be more of making sure your sensors are set right.

Thank you.

We are changing our filters every 2-3 days of use (100gal of prod/day). The (boost?) pressure drops from ~18psi to ~1psi. If we continue, the feed pump doesn't sound happy -- so I don't think it is (just) a sensor issue. The pressure returns to ~18psi with a new 5 micron filter, but only for a couple of days.

The Spectra factory support (Jean) endorsed the use of pre-fitlers between the boost and feed pump -- this is where the filters they sell go.

[bensolomon]

Tellie,

In the Chesapeake (my home waters, there is a ton of particulate matter in the water, constantly: Farm runoff, plant material, Elodea blooms, etc. I wouldn't think it would be good to run a water maker in that environment.

[Tellie]

Originally Posted by accomplice

Thank you.

We are changing our filters every 2-3 days of use (100gal of prod/day). The (boost?) pressure drops from ~18psi to ~1psi. If we continue, the feed pump doesn't sound happy -- so I don't think it is (just) a sensor issue. The pressure returns to ~18psi with a new 5 micron filter, but only for a couple of days.

The Spectra factory support (Jean) endorsed the use of pre-fitlers between the boost and feed pump -- this is where the filters they sell go.

With all due respect to Jean the boost pressure will rise with a dirty pre-filter because the existing 5 micron prefilter is between the boost pump and the feed pump. When the filter gets dirty it's like placing your thumb over your garden hose. The pressures will rise and the flow will be restricted. If your boost pump pressure are dropping off to 1psi in any scenario you have another issue other than the filters.

[accomplice]

Originally Posted by Tellie

With all due respect to Jean the boost pressure will rise with a dirty pre-filter because the existing 5 micron prefilter is between the boost pump and the feed pump. When the filter gets dirty it's like placing your thumb over your garden hose. The pressures will rise and the flow will be restricted. If your boost pump pressure are dropping off to 1psi in any scenario you have another issue other than the filters.

It is the pressure measured after the filter that drops -- from about 18psi towards zero, and then goes back to 18psi with a new filter. How does that point to anything but a filter issue?

[Tellie]

Originally Posted by bensolomon

Tellie,

In the Chesapeake (my home waters, there is a ton of particulate matter in the water, constantly: Farm runoff, plant material, Elodea blooms, etc. I wouldn't think it would be good to run a water maker in that environment.

That's what I've heard about the water quality. Every year after the Annapolis boat show within a few months I start getting a few calls from people heading down this way who have run their new watermakers, Spectras and other brands in the Chesapeake, and the ICW. Even the best pre-filters don't seem to always protect the watermakers in that environment. You are correct, running them there is usually not a good idea. As I stated before. Watermakers are an offshore piece of equipment. If people want to run them in these environments please take my number down. We have a really great service techs down here.

[Tellie]

Originally Posted by accomplice

It is the pressure measured after the filter that drops -- from about 18psi towards zero, and then goes back to 18psi with a new filter. How does that point to anything but a filter issue?

I don't mean to be picky about the wording but sometimes it makes a difference. You stated the boost pump pressure drops. That's what I was addressing. Certainly a dirty filter will show lower pressures on the output side of the pre-filter. That's where the sensor is. But that is not boost pressure. Your system is experiencing a vacuum, that's why your feed pump is complaining. Where are you operating your watermaker again?

[accomplice]

Originally Posted by Tellie

That's what I've heard about the water quality. Every year after the Annapolis boat show within a few months I start getting a few calls from people heading down this way who have run their new watermakers, Spectras and other brands in the Chesapeake, and the ICW. Even the best pre-filters don't seem to always protect the watermakers in that environment. You are correct, running them there is usually not a good idea. As I stated before. Watermakers are an offshore piece of equipment. If people want to run them in these environments please take my number down. We have a really great service techs down here.

In my case, I cannot blame water quality. In the same and similar environments the SeaRecovery ran for thousands of gallons of product with a (larger) 5 micron filter before the filter needed changing.

[accomplice]

Originally Posted by Tellie

You stated the boost pump pressure drops. That's what I was addressing. Certainly a dirty filter will show lower pressures on the output side of the pre-filter. But that is not boost pressure. Where are you operating your watermaker?

Gulf of Maine, Penobscot Bay, Casco Bay.

The water is fundamentally no different than the water into the old water-maker. I have removed the commercial oil pre-filter to ease the load on the spectra boost pump.

Certainly if the water contained no particulate matter then the filters wouldn't get clogged -- but that's the nature of *clean* seawater in many areas, including offshore.

[Tellie]

Originally Posted by accomplice

Gulf of Maine, Penobscot Bay, Casco Bay.

The water is fundamentally no different than the water into the old water-maker. I have removed the commercial oil pre-filter to ease the load on the spectra boost pump.

Certainly if the water contained no particulate matter then the filters wouldn't get clogged -- but that's the nature of *clean* seawater in many areas, including offshore.

Of course that's true. Remember though a Spectra is a whole lot different in design than a plunger pump type watermaker. It is meant to be very energy efficient and built into that design are flows and pressure that reflect that energy efficiency. But if you are running in an environment that is so heavy in particulates that it is clogging your prefilter that quickly and consistently, I would advise not running it there at all. As I mentioned earlier, even the best pre-filters are not 100% perfect. Particulates can and will get past these pre-filters and work their way into your Clark pump with it's fairly close tolerances and certainly into your membrane where the real trouble begins. Any particulates that a larger pre-filter will catch will easily be caught by the five micron filter on your system. You could put another 20 Micron pre-filter in front of the 5 Micron but I assure you, the 5 Micron will clog up just about as quick. The only real answer to these situations if a person insists on running in these environments is a sediment filter. But this on a Catalina 340 will require a bit of modifications and a few extra bucks. I know what you paid for this watermaker, and as humbly as possible I would gently consul you to heed my advice.