RO Prefilters

[Amber Gold]

I recently switched to 20" prefilters that I got from FW Webb...their brand of 5 micron filters. They work fine until I switch to a wash cycle, the filter clogs up within a couple of minutes and shuts the RO off. Fortunately I still had a leftover PURTREX that I've been able to swap in for the wash cycle. I use the Lapierre Sodium Hydroxide wash soap. They're great because they're cheap, but not worth it if I can't go through a full day. Also, now that we're into the cloudy sap, they clog up faster than the Purtrex filters did, and they don't look that dirty. Since the filters are cheap, <$3, I put a new filter in every time.

Has anyone else had a similar issue with these filters?

Thanks

[mapleack]

Good to know, I've been using them the second half of the season but never tried to wash with one, I too had purtrex from last season, I use the same filter to wash the whole season, storing it in a pvc tube when not in use. I haven't tried to wash with one of the ones from Webb.

[sapman]

I tried a different brand for awhile cause I could get them through where I work. Think they were Pentek or something. But they didn't seem to last as long, either. I've gone back to the GE filters myself.

Do you find the sodium hydroxide works better? Is it powder, replacing what's normally used in Filmtec/Fluid System?

[twofer]

Are you swapping out the filter for cleaning or using the same one?

[sapman]

I just use the same ones all the time til they foul.

[twofer]

I just use the same ones all the time til they foul.

So just to be clear, you use the same filter for concentrating and washing until it clogs?

If you are doing it that way how many concentration cycles are you getting out of the filter before it clogs?

[Amber Gold]

When I was using the purtrex filters, I put a new one in and it'd be in there from the very start through the final rinse cycle. I'd start the next day with a new filter. I figured these Webb filters are so cheap, it wasn't worth the hassle of setting one aside for a wash cycle.

I'm using the powedered sodium hydroxide, and thinking of which, does anyone else have a problem with this foaming a lot? The foam usually boils out of the top of the wash tank and I use about 1oz. per wash cycle.

[Russell Lampron]

I don't know what brand they are but I use the pre filters that Joe sells at Atlantic RO. I use the Lapierre cloth wraps and use a pre filter until the feed pump pressure drops or until I can see the discoloration in the center core of the filter. I save the first filter of the season and swap it in to do the wash cycles.

I use the powered sodium hydroxide and it does make a lot of foam I only fill my wash tank about 3/4 full and the foam doesn't overflow the tank but it is difficult to get a ph reading.

[Jeff E]

It was mentioned a bit, but it was directed from CDL to not wash/rinse with the same prefilter used for concentrating.
I also use 1 filter all season for the wash and long rinse following a wash.
A new filter for each concentration cycle.

[Mark]

If you can't rinse the caustic from the prefilter how can it be rinsed from the membrane?

[Jeff E]

I am not sure it has to do with the inability of getting the filter clear of the cleaning agents, as it a matter insuring the cleaning filter is not loading up and limiting the flow rate. I know it is a simple matter to have a clean filter to reuse for the wash cycle, so I went with it without questioning the process...

[Brent]

Josh
if a filter is working it is collecting gunk on the surface .... and clogging up.

if a filter is not working some of the gunk is passing through .... and not clogging up.

the best filter is the one that removes the gunk and clogs up, unless of coarse you measure
the usefulness of a filter by the low numbers on your credit card instead of the junk on the filter.

[sapman]

Early in the season I can concentrate maybe 4-6 times on the same filters. I should add mine has double-stacked 20". Later, probably 1 or 2 concentrations.

[Amber Gold]

Even though both the Webb and GE filters are both 5 micron, the Webb one's look much finer and are smoother. Now that I'm into snottier sap, they're fouling much quicker as well. I wrapped my filter last night, took the wrap off, ran for a bit and had to put a new filter in, and still barely made it through the night. I've had much worse sap than this before and never had to swap filters like this. Once the season ends, these will be going back and I'll be getting something else.

Russ, can you find out what brand Joe sells?

[mapleack]

Josh, are you filtering your sap with a bag filter first? I'm not using wraps and haven't had one of the webb filters foul before one day was over yet.

[Amber Gold]

Yes. Filtered as it goes into the truck tank, and filtered again as it goes into the SH sap tank. Can you find out what filter's you're using? Maybe I have the wrong one's, or I got a bad batch. I heard a few years ago Lapierre had a bad batch and was having pressure problems with the filters they were selling, so it's possible.

[Russell Lampron]

Josh I'll look tonight. I don't remember seeing a name on the wrapper. He sent them to me in a generic box so there was no name brand on it either.

[sapman]

I got two cases from Joe last week. They are GE Purtrex PX05-20(5 micron, 20 inch). These look the same as ones I got from Bascom's years ago. The others I tried for awhile sound like the ones you got, Josh, that are smooth and hard. Different material.

[Amber Gold]

Tim, how much are PX-05's from Joe? I think Lapierre charges $7 or so. You're right on the one's from Webb...it's their house brand.

[sapman]

Josh, $3.80 + shipping, which was $23 for two cases (so $4.38). Not sure what brand they offer, but CDL lists them for $4.20, which ends up being cheaper if you pick them up at the store.

[Amber Gold]

I'll be in St. Albans in a couple of weeks. I"ll pick a couple cases up then. Thanks Tim.

[batsofbedlam]

20" Purtrex Sediment Depth Filter - 10 Mic (PX10-20) are $165.36 for two cases and $1.99 shipping at Freshwatersystems.com

[Russell Lampron]

Russ, can you find out what brand Joe sells?


Josh, $3.80 + shipping, which was $23 for two cases (so $4.38). Not sure what brand they offer, but CDL lists them for $4.20, which ends up being cheaper if you pick them up at the store.

I checked the filters that I got from Joe and they are the Purtrex PX05-20. Like Tim said $3.80 each plus shipping. The last time that I bought some from Lapierre they were around $6 each and that was a couple of years ago.

[maple flats]

I'll need to check the number tomorrow, but I think mine are the Purtrex PX05-20. My last case from Ray Gingerich were $3.00 ea + actual UPS. For concentrating I use them until they start to clog, for a soap wash or Acid wash, I change them after each time. Again, I'll need to verify the name and number.

[sapman]

That is a great price!

[Amber Gold]

The one's I got from Webb are PurePro 5 micron filters...just realized these say dirt and rust cartridge vs. sediment cartridge like the Puretrex one's do. I wonder if that's why the weave is different. I think due to competition, Lapierre's come down on price. Their catalogue advertises $3.89 each.