[dazmond]

These are just under £25 for the 2(carbon and sediment). No info on how long they last or how often they should be changed( PF just say regularly). My pre filter housing is black plastic so I can't see at a glance when they need changing.

I was thinking every 4 months and I've noted it on my Google calendar

The fibredyne filters from Daqua are over twice the price. The question is are the PF ones good enough? They use them in all their 4040 systems....

Thanks in advance chaps!

[Spruce]

These are just under £25 for the 2(carbon and sediment). No info on how long they last or how often they should be changed( PF just say regularly). My pre filter housing is black plastic so I can't see at a glance when they need changing.

I was thinking every 4 months and I've noted it on my Google calendar

The fibredyne filters from Daqua are over twice the price. The question is are the PF ones good enough? They use them in all their 4040 systems....

Thanks in advance chaps!

If only we knew how much chlorine was actually in our tap water every hour of the day it would make this question so easy to answer.

But we don't know. So I made the decision to replace my Fiberdyne carbon block according to the manufacturers recommendations. Pentair advise to replace their 20" filters every 75700 litres of water which includes waste and pure. I change mine every 77,000 litres and I'm still on the same HF5 membrane I started with.

If Purefreedom won't give a service life on their c/b filters, then I would purchase elsewhere. I still have a 20" GAC -20R-C coconut shell carbon filter under my desk. It has a service life of 2500 US gallons (10,000 litres.) I've seen specs for a service life of 12,000 litres and 18,000 litres for other c/b filters. (At 18k I would need to change filters every 4 weeks).

I fitted 2 pressure gauges, one on each side of the prefilters. The first gauge measures the water pressure at the sediment filter. The second measures the pressure after the c/b filter. When there is a difference of 10psi, its time to change the sediment filter. The Spectrum sediment filter catches all the sediment above 5 micron The Fiberdyne c/b will let particles through up to 10 micron. So the c/b filter will never get blocked due to sediment. It will always be the sediment filter.
I have a separate water meter on my r/o so I know when to replace my prefilters.

My previous 450gpd membranes lasted 6 years with me replacing them every 3 months. I didn't buy Fiberdyne back then.

I originally purchased that r/o second hand from a local window cleaner. The r/o was a year old and he had never replaced his prefilters in that year. He replaced them for me. But those membranes were shot. Same water. So I know I can't leave my carbon block filter for a year.

According to Doug Atkinson of Daqua, his Refyne carbon block filters will last 105,000 litres with the same chlorine level the Pentair quote their Fiberdyne lasting for 75700 litres.

At one time I would have changed to his Refyne filters, but I now also consider the cost of a new HF5 membrane and what has worked for me. I see he also has a proviso that "in some cases service life will not be reached if high content of Chlorine or Sediment is in the supply water."
This makes sense, but there is no clause like this in Pentairs instructions.

[windowswashed]

water production slows down a lot when the fibredyne filter starts clogging up, that's when I know it's time to discard and replace with new filter approximately 3-4 months max

[martinw]

From my own personal experience with fibredyne  blocks these are rated 2ppm and 7lpm flow as per literature, most of uk water supplies are roughly 0.1-0.5ppm of chlorine - this can be verified on your water supplier website by postcode. In reality these filters will last much longer.  In my case it seems 2-3 times rated value is a sweet spot. Membrane is now three years old and still takes 320-350 down to 6-8 ppm, never been flushed either making up to 150-180 l /hr slowly starts showing signs of wear. Food for thought…

[colin bird]

Hi daz but them from finer filters £35 ish for three sets of two going from memory no deliver charge,there web site is a bit difficult so I just phone them.

I change mine when my tds starts to rise,also change resin at the same,this is what I’ve done for the last sixteen years not saying I’m right but that’ works for me

[dazmond]

I'm a bit annoyed that there is no information on these PureFreedom filters on their website as it sounds like it's a very important part of keeping your RO membrane in good condition but I'm sure PF wouldn't install rubbish filters on their high volume 4040 systems.

 I use approx 1600-2000L per week as I only work 4 short days every week.

Maybe I'm overthinking it. I think I'll order 3 sets for the next year and just change every 4 months and see how I go on. It's an expensive mistake though if my membrane is shot after a year as they are currently around £470 to replace!

[dazmond]

After doing a bit more research I've found out that PureFreedom use PENTAIR CBR210 carbon block filters in their high volume systems which have a 75708L service life which is ideal for changing them every 4 months.

Thanks for your input lads!🙂👍

[martinw]

Couple questions to more knowledgeable folks :
Is there benefit to have 1micron or 0.5 micron block for our use?
Why one would choose or consider picking this finer filter over 5 when we are not using it for drinking water?

Daz these are rated 3.8lpm  flow rate therefore lifespan will be shorter than you may think by the looks of specs. Also sediment filter will need more frequent changes to avoid clogging.

Please correct me if I’m wrong here … always willing to learn something new

[Spruce]

Couple questions to more knowledgeable folks :
Is there benefit to have 1micron or 0.5 micron block for our use?
Why one would choose or consider picking this finer filter over 5 when we are not using it for drinking water?

Daz these are rated 3.8lpm  flow rate therefore lifespan will be shorter than you may think by the looks of specs. Also sediment filter will need more frequent changes to avoid clogging.


Please correct me if I’m wrong here … always willing to learn something new

I once tried a 1 micron carbon block filter. I found that it clogged up with sediment and become unusable about 1/2 way through it's stated service life. 12 years ago that filter from Osmotics cost 3 times what the equivalent Fiberdyne filter did.  For me, it was an expensive path which I tried and learnt that it didn't work for me.

The other thing I didn't consider that our water back then was sometimes laden with sediment. I often had to replace the sediment filter 3 times to once with the carbon block filter. All of us wfp window cleaners in our local area experienced the same issue.

[Perfect Windows]

We use DI vessels with activated carbon granules in them as a combined chlorine and particle filter.

25kg sack about £200* gives five refills, each lasts a year with no problems.

Vin

* Used to be about £70. Then someone came up with the barmy theory that it soaks up "toxins" in your food, so absolute codpieces started to eat it and the price ballooned. It soaks up vitamins as well but apparently that's OK.

[Spruce]

We use DI vessels with activated carbon granules in them as a combined chlorine and particle filter.

25kg sack about £200* gives five refills, each lasts a year with no problems.

Vin

* Used to be about £70. Then someone came up with the barmy theory that it soaks up "toxins" in your food, so absolute codpieces started to eat it and the price ballooned. It soaks up vitamins as well but apparently that's OK.

I have often wondered if you still did this.

[martinw]

Vin is that year for each di vessel refill or per 25kg sack?
I’m assuming you must have some fine mesh filter to stop carbon granules from flowing out of vessel under pressure?

Another thing comes to  my mind with those low flow rated filter is to try to put two of them or more in parallel to obtain desired flow rates for 4040.   

[Perfect Windows]

Vin is that year for each di vessel refill or per 25kg sack?
I’m assuming you must have some fine mesh filter to stop carbon granules from flowing out of vessel under pressure?

Another thing comes to  my mind with those low flow rated filter is to try to put two of them or more in parallel to obtain desired flow rates for 4040.   

Should have been clearer, sorry.

Sack gives about five refills. Each refill lasts a year without problems. Five years from a sack.

Used to use acid washed charcoal - almost no fine charcoal particles escape but one of the franchisees just used normal charcoal and had no problems.

Vin