5 micron watermaker prefilter cleaning

[Fuss]

Roughly speaking the 5 micron filter needs cleaning once a week or after making 150 Liters.
I have generally found that this filter can be reused about 8 times if you have enough water pressure when cleaning it.
Enough water pressure means around 3-4 bar.
If you have around 1-2 bar then the filter can only be re-used about 3-4 times.
So my questions are...
how many times can you reuse your 5 micron filter?
How many liters can your watermaker make before the 5 micron needs cleaning?
How do you clean your 5 micron filter?
If you have 3-4 bar fresh water pressure available, how are you doing it.?
Thanks John

[captainjay]

We have several water makers in the charter fleet. We added 20 micron filters before the 5 microns it helps a lot.

[SV THIRD DAY]

We tell our clients that the pleated polyester prefilter can be cleaned 3-4 times before we toss it out and put in a new prefilter. For cleaning Never use any soaps or chemicals because any residue will get into the membrane. I have found that a vigorous slosh in a bucket of sea water followed by a fresh water rinse and life line dry (for UV) does a good job of cleaning.
As for frequency, that totally depends on if you are making water in Crystal clear water vs the Charlie and the Chocolate Factory river!

[Tellie]

Originally Posted by Fuss

Roughly speaking the 5 micron filter needs cleaning once a week or after making 150 Liters.
I have generally found that this filter can be reused about 8 times if you have enough water pressure when cleaning it.
Enough water pressure means around 3-4 bar.
If you have around 1-2 bar then the filter can only be re-used about 3-4 times.
So my questions are...
how many times can you reuse your 5 micron filter?
How many liters can your watermaker make before the 5 micron needs cleaning?
How do you clean your 5 micron filter?
If you have 3-4 bar fresh water pressure available, how are you doing it.?
Thanks John

I think the bigger and more important question is why it needs to be changed so often. You should be getting a lot more use from a pre-filter than 150 liters (39.5 gallons) before it needs to be cleaned.

[Fuss]

Originally Posted by Tellie

I think the bigger and more important question is why it needs to be changed so often. You should be getting a lot more use from a pre-filter than 150 liters (39.5 gallons) before it needs to be cleaned.

yes, you are absolutely correct...well spotted... I really meant around 1500 Liters.

The normal tap pressure is not really enough to clean it and it needs around 4 bar pressure to clean it properly.

As I considered that most boats tap water pressure would not be too different to mine, I was wondering what they were using to clean this 5m filter. (The 20 micron is easy as it does not need much water pressure).

[chuckr]

we tie a string to ours and throw it over board -- be surprised how clean it will get.

[Tellie]

Originally Posted by chuckr

we tie a string to ours and throw it over board -- be surprised how clean it will get.

I used to recommend this as well. Thread a line through the middle of the filter and tie a safety knot on the end and toss it over board and tow the filter. But not any more. You are actually reversing the direction of water flow through the middle interior of the filter. So the water is flowing both on the outside of the filter side you are trying to clean and forcefully flowing into the center of the filter and the wrong side of the filter media. In effect you are reversing the direction of flow and filtering the water you are dragging it through backwards. With the safety knot effectively blocking the back end of the filter as it's being dragged, everything and anything that enters the other end of the filter facing the flow is forced into the filter media inside the center. When you place the filter back into your system and start it anything you have trapped on the inside of the filter is now going to be flushed back into your watermaker unfiltered. I learned this the hard way on a brand new watermaker a customer depended on to sail around the world with. His was an extreme example as he caught a very small flying fish inside his filter and it was mushed up pretty good. Not thinking of looking inside the filter, and after taking my advice to clean the filter this way, he placed the filter back into the system. It took us two months, several attempts at disassembling the unit, cleaning, and two new membranes sent to the south Pacific before we finally figured it out.

Halden Marine Services | Marine Watermakers, Solar Panels, Wind Generators
(954) 515-7077

[senormechanico]

I have two polyester filters (supposedly original to the Spectra 180).
As I am not the original owner, I'm not sure of that, but when they get grungy looking I stand them on end and irrigate them through the top hole.
If I'm at a dock I flush for about a minute, but on the boat I shorten that to about 30 seconds, fresh water of course.
The deck stops the water from leaking out the bottom and the whole filter pleats get reverse flushed.
They bow out a bit, but not enough to hurt them.
I leave them out in the sun to dry before storing.
When in cruising mode, I switch them back and forth between the sun drying /storage and "in service".
I've done this for years, and they seem just fine.

[Reefmagnet]

Originally Posted by Tellie

I used to recommend this as well. Thread a line through the middle of the filter and tie a safety knot on the end and toss it over board and tow the filter. But not any more. You are actually reversing the direction of water flow through the middle interior of the filter. So the water is flowing both on the outside of the filter side you are trying to clean and forcefully flowing into the center of the filter and the wrong side of the filter media. In effect you are reversing the direction of flow and filtering the water you are dragging it through backwards. With the safety knot effectively blocking the back end of the filter as it's being dragged, everything and anything that enters the other end of the filter facing the flow is forced into the filter media inside the center. When you place the filter back into your system and start it anything you have trapped on the inside of the filter is now going to be flushed back into your watermaker unfiltered. I learned this the hard way on a brand new watermaker a customer depended on to sail around the world with. His was an extreme example as he caught a very small flying fish inside his filter and it was mushed up pretty good. Not thinking of looking inside the filter, and after taking my advice to clean the filter this way, he placed the filter back into the system. It took us two months, several attempts at disassembling the unit, cleaning, and two new membranes sent to the south Pacific before we finally figured it out.

Halden Marine Services | Marine Watermakers, Solar Panels, Wind Generators
(954) 515-7077

Makes sense. If one were to make a threaded rod with two end caps for use as a sealing plug for the filter, and that also incorporated an eye to allow for attaching the line, do you think that could that work?

Sent from my SGP521 using Cruisers Sailing Forum mobile app

[Paul L]

Originally Posted by Fuss

yes, you are absolutely correct...well spotted... I really meant around 1500 Liters.

The normal tap pressure is not really enough to clean it and it needs around 4 bar pressure to clean it properly.

As I considered that most boats tap water pressure would not be too different to mine, I was wondering what they were using to clean this 5m filter. (The 20 micron is easy as it does not need much water pressure).

We use two methods. The tow behind on a line and then sit in the sun's UV. Have not had any issues with getting fish stuck in the interior The other approach uses the saltwater anchor wash down. I stick the hose in the top and cover the bottom with my hand, forcing a reverse flow on the filter. Then use the high pressure to spray the exterior, followed by a sun bake.
I have two filters that I swap back and forth over a long season, then replace for the next year.

[Capt. Aubrey]

PM sent. Thx.

[sailjumanji]

My saltwater wash down pump only has a strainer on it, not a filter. Would think you could get some good-sized debris inside the filter and into your membrane with that. Although I could see using it at angle on the filter ezterior.

So did we get a spectra dealer recommended cleaning method? JT?

[Paul L]

Originally Posted by sailjumanji

My saltwater wash down pump only has a strainer on it, not a filter. Would think you could get some good-sized debris inside the filter and into your membrane with that. Although I could see using it at angle on the filter ezterior.

So did we get a spectra dealer recommended cleaning method? JT?

It's been working OK for me over the last 5 years full time. If you are really picky about your filtering then you can replace the filters more often. It's only money and storage space.

[Tellie]

Originally Posted by senormechanico

I have two polyester filters (supposedly original to the Spectra 180).
As I am not the original owner, I'm not sure of that, but when they get grungy looking I stand them on end and irrigate them through the top hole.
If I'm at a dock I flush for about a minute, but on the boat I shorten that to about 30 seconds, fresh water of course.
The deck stops the water from leaking out the bottom and the whole filter pleats get reverse flushed.
They bow out a bit, but not enough to hurt them.
I leave them out in the sun to dry before storing.
When in cruising mode, I switch them back and forth between the sun drying /storage and "in service".
I've done this for years, and they seem just fine.

(supposedly original to the Spectra 180)!!!!!!! Those have to be at least 15 years old you old cheap...uh,... sailor.. Shoot me a PM with your address and I'll send you a few new ones on me. Really, it's time.

Halden Marine Services | Marine Watermakers, Solar Panels, Wind Generators
(954) 515-7077

[Tellie]

Originally Posted by Paul L

It's been working OK for me over the last 5 years full time. If you are really picky about your filtering then you can replace the filters more often. It's only money and storage space.

PS, You too Paul.


Halden Marine Services | Marine Watermakers, Solar Panels, Wind Generators
(954) 515-7077