MisterC

  • Posts: 63
When to change RO Membrane
« on: September 25, 2014, 09:30:54 am »
My system is just over 12 months old and have noticed I am having to change resin about once every three weeks to keep TDS under 5, I am gradually doing more work as I build up my round but when I first got my system I went for 6 months before needing to change resin. I am flushing system once a week but not for the hour that the manufacturer recommends as it seems over the top. Does this mean I need to change my membrane, the system is from Brodex (yes I know) they want £285 for a new membrane, can they be got cheaper from another supplier.
Thanks for any advice guys.

Window Lickers

  • Posts: 2196
Re: When to change RO Membrane
« Reply #1 on: September 25, 2014, 09:44:11 am »
Have you changed your prefilters?
Liberace's ex looking to meet well built men for cottaging meets.

SeanK

Re: When to change RO Membrane
« Reply #2 on: September 25, 2014, 10:38:22 am »
What's the TDS from the R.O. alone that's what you need to know.
What's the TDS from your tap water.
To be honest I think there is something wrong with your system if that's the kind of lifespan
your getting from both membrane and resin.
It just shows how bad a company Brodex really are when they are not pointing this out to you.
Going by the price of the membrane I would say its a 4040 and you can get them cheaper than that.

If the TDS is high coming from the R.O. then you need to firstly check if your water pressure is high enough.
Is your water hard (do your get scale in your kettle and teapot) this can ruin a R.O. so you will need a water
softener.



MisterC

  • Posts: 63
Re: When to change RO Membrane
« Reply #3 on: September 25, 2014, 11:23:58 am »
Water from the tap is about 350 TDS, pressure is good but I am in a hard water area.
I have not changed the prefilters, is that a good place to start ?

soapsudtw

  • Posts: 16
Re: When to change RO Membrane
« Reply #4 on: September 25, 2014, 12:48:51 pm »
350 is high.
You really need a water softening vessel before the system with that kind of tds.
12 months is about right for the conditions it's had to work in
As said check the tds from the RO first, if its over 35 then it's knackered :D

What do you call good pressure? do you have a value?
Less than 40 psi and it won't work very efficiently at all

MisterC

  • Posts: 63
Re: When to change RO Membrane
« Reply #5 on: September 25, 2014, 02:03:09 pm »
Thanks for your advice guys

Ian Lancaster

  • Posts: 2811
Re: When to change RO Membrane
« Reply #6 on: September 25, 2014, 03:06:33 pm »
Water from the tap is about 350 TDS, pressure is good but I am in a hard water area.
I have not changed the prefilters, is that a good place to start ?

That could be the problem.  Prefilters should have the expected life printed on them, usually something like 'Every six months or xxxxxxthousand litres' 

It would be helpful if you told us how much water you are producing, what your water pressure is (just because it looks good, doesn't mean it is) and what size DI vessel you have.

SeanK

Re: When to change RO Membrane
« Reply #7 on: September 25, 2014, 04:36:07 pm »
Yes change the pre filters but I doubt that's the problem, you still need to know what the tds from the
R.O. is.
This will tell you if your problems the membrane or the resin.

Ian101

  • Posts: 7887
Re: When to change RO Membrane
« Reply #8 on: September 25, 2014, 04:59:34 pm »
at what level tap tds would a water softener be appropriate ??

MisterC

  • Posts: 63
Re: When to change RO Membrane
« Reply #9 on: September 25, 2014, 05:03:16 pm »
Producing about 250litres each weekday, DI vessel is 10 litres, don't know what water pressure is, don't have anything to measure it. Will check TDS from RO, if it is knackered where would you advise buying new one from. Thanks

chez

Re: When to change RO Membrane
« Reply #10 on: September 25, 2014, 05:04:59 pm »
I agree you should find out what the TDS is coming out of the RO but before the resin. Mine comes out about 14 with a tap tds at 280. If it is in the 30's then you really do have to get a new RO. But the main problem I see for you is that the prefilters aren't doing their job or not changing them enough which is knackering your RO too soon. I have a Brodex system which is simply superb. However when I bought it they only have one prefilter fitted which was either a sediment or a carbon. It's not sufficient and reported back to them. So I swapped over to the fibredine which does protect the RO much better and you don't have to change them so much either,  hence the RO should last 1 and a half to 2 years. I go through about 1500 to 2000 litres per week.
Hope it helps!
Cheers Chez

chez

Re: When to change RO Membrane
« Reply #11 on: September 25, 2014, 05:07:41 pm »
Ps..... I flush the RO for about 10 to 15 mins after each tank full rather than once a week. Better to keep the RO in top condition as it will last longer that way.

MisterC

  • Posts: 63
Re: When to change RO Membrane
« Reply #12 on: September 25, 2014, 05:37:38 pm »
Thanks for all your advice guys, will check TDS at RO and change pre filters.

Jonny 87

  • Posts: 3483
Re: When to change RO Membrane
« Reply #13 on: September 25, 2014, 05:52:00 pm »
Glad to see brodex are letting their customers know how to maintain the systems.

 ???
Vision Technician / Visual Engineer /  Vision Enhancement Operative /...........................................................OnlyUseMeWFP AkA Jonny the Windy Wesher

martin hulstone

  • Posts: 323
Re: When to change RO Membrane
« Reply #14 on: September 25, 2014, 06:25:14 pm »
Dont buy a water softener, it will cost you more in salt than replacing a membrane every couple of years, it also drops your pressure as it is yet another vessel for the water to pass through.

Window Lickers

  • Posts: 2196
Re: When to change RO Membrane
« Reply #15 on: September 25, 2014, 06:36:00 pm »
What about an electronic water softener?
Liberace's ex looking to meet well built men for cottaging meets.

SeanK

Re: When to change RO Membrane
« Reply #16 on: September 25, 2014, 07:21:35 pm »
I agree you should find out what the TDS is coming out of the RO but before the resin. Mine comes out about 14 with a tap tds at 280. If it is in the 30's then you really do have to get a new RO. But the main problem I see for you is that the prefilters aren't doing their job or not changing them enough which is knackering your RO too soon. I have a Brodex system which is simply superb. However when I bought it they only have one prefilter fitted which was either a sediment or a carbon. It's not sufficient and reported back to them. So I swapped over to the fibredine which does protect the RO much better and you don't have to change them so much either,  hence the RO should last 1 and a half to 2 years. I go through about 1500 to 2000 litres per week.
Hope it helps!
Cheers Chez

That's the problem Chez you think the Brodex is simply superb but at a tap tds of 280ppm there's no reason why you shouldn't get
your tds down to 3ppm.
Also a membrane should easily last 5 years before breaking down especially with such a low tap tds.
I certainly wouldn't class them as a superb system by any means.

 

SeanK

Re: When to change RO Membrane
« Reply #17 on: September 25, 2014, 07:31:52 pm »
Flush the R.O. for 5 to 10mins before making pure and then slowly close of the waste tap until the R.O. starts
to make pure this stops what is known as R.O. shock.
I honestly believe that R.O. shock is the biggest reason for premature R.O. failure.
This is how the industrial guys run their systems cant see why we shouldn't do the same as we just purify the
water on a smaller scale.

Avo

  • Posts: 1634
Re: When to change RO Membrane
« Reply #18 on: September 25, 2014, 09:45:35 pm »
My system is just over 12 months old and have noticed I am having to change resin about once every three weeks to keep TDS under 5, I am gradually doing more work as I build up my round but when I first got my system I went for 6 months before needing to change resin. I am flushing system once a week but not for the hour that the manufacturer recommends as it seems over the top. Does this mean I need to change my membrane, the system is from Brodex (yes I know) they want £285 for a new membrane, can they be got cheaper from another supplier.
Thanks for any advice guys.
which brodex system you got?

There's a number of problems here misterc.
X1 sediment filter is not enough protection for your membrane because u only have one 10" filter housing you need to start putting in CFB-PLUS Sediment/Carbon filters to help protect your system.
Unplug your di on the inlet side and plug a hose into the female connection then run your RO system into a bucket taking readings from the membrane, keep closing your waste until you get the lowest reading from your RO brodex will tell the to run your system at 1.5 litres pure WRONG this simply is rubbish it will run higher Tds like this hence killing your resin.

chez

Re: When to change RO Membrane
« Reply #19 on: September 26, 2014, 08:03:04 am »
I agree you should find out what the TDS is coming out of the RO but before the resin. Mine comes out about 14 with a tap tds at 280. If it is in the 30's then you really do have to get a new RO. But the main problem I see for you is that the prefilters aren't doing their job or not changing them enough which is knackering your RO too soon. I have a Brodex system which is simply superb. However when I bought it they only have one prefilter fitted which was either a sediment or a carbon. It's not sufficient and reported back to them. So I swapped over to the fibredine which does protect the RO much better and you don't have to change them so much either,  hence the RO should last 1 and a half to 2 years. I go through about 1500 to 2000 litres per week.
Hope it helps!
Cheers Chez

That's the problem Chez you think the Brodex is simply superb but at a tap tds of 280ppm there's no reason why you shouldn't get
your tds down to 3ppm.
Also a membrane should easily last 5 years before breaking down especially with such a low tap tds.
I certainly wouldn't class them as a superb system by any means.

 
Thanks for your opinion, which is all it is an opinion. I just gave mine that I'm am very happy with my system. ROs normally operate with a 5% margin, so as my tds tends to fluctuate between 280 and 320, and taking in to consideration water quality and water pressure, mine isn't particularly good, and as long as I get between 10 and 14 it's great. I've noticed many on here struggle to get the basic 5% efficiency, but mine consistently has from the day I bought it 5 years ago......happy days!

Avo

  • Posts: 1634
Re: When to change RO Membrane
« Reply #20 on: September 26, 2014, 08:12:22 am »
I agree you should find out what the TDS is coming out of the RO but before the resin. Mine comes out about 14 with a tap tds at 280. If it is in the 30's then you really do have to get a new RO. But the main problem I see for you is that the prefilters aren't doing their job or not changing them enough which is knackering your RO too soon. I have a Brodex system which is simply superb. However when I bought it they only have one prefilter fitted which was either a sediment or a carbon. It's not sufficient and reported back to them. So I swapped over to the fibredine which does protect the RO much better and you don't have to change them so much either,  hence the RO should last 1 and a half to 2 years. I go through about 1500 to 2000 litres per week.
Hope it helps!
Cheers Chez

That's the problem Chez you think the Brodex is simply superb but at a tap tds of 280ppm there's no reason why you shouldn't get
your tds down to 3ppm.
Also a membrane should easily last 5 years before breaking down especially with such a low tap tds.
I certainly wouldn't class them as a superb system by any means.

 
Thanks for your opinion, which is all it is an opinion. I just gave mine that I'm am very happy with my system. ROs normally operate with a 5% margin, so as my tds tends to fluctuate between 280 and 320, and taking in to consideration water quality and water pressure, mine isn't particularly good, and as long as I get between 10 and 14 it's great. I've noticed many on here struggle to get the basic 5% efficiency, but mine consistently has from the day I bought it 5 years ago......happy days!
hi chez which membrane do you run?

Spruce

  • Posts: 8366
Re: When to change RO Membrane
« Reply #21 on: September 26, 2014, 08:25:18 am »
Water from the tap is about 350 TDS, pressure is good but I am in a hard water area.
I have not changed the prefilters, is that a good place to start ?

That could be the problem.  Prefilters should have the expected life printed on them, usually something like 'Every six months or xxxxxxthousand litres' 

It would be helpful if you told us how much water you are producing, what your water pressure is (just because it looks good, doesn't mean it is) and what size DI vessel you have.

This is the issue which has been identified by Ian and his years of experience.

The chlorine block filter removes chlorine from the water as chlorine destroys membranes. Chlorine block filters only have a limited life.

The prefilters need to be replaced inline with the manufacturers directions.

Success is 1% inspiration, 98% perspiration and 2% attention to detail!

The older I get, the better I was ;)

chez

Re: When to change RO Membrane
« Reply #22 on: September 26, 2014, 03:40:24 pm »
I agree you should find out what the TDS is coming out of the RO but before the resin. Mine comes out about 14 with a tap tds at 280. If it is in the 30's then you really do have to get a new RO. But the main problem I see for you is that the prefilters aren't doing their job or not changing them enough which is knackering your RO too soon. I have a Brodex system which is simply superb. However when I bought it they only have one prefilter fitted which was either a sediment or a carbon. It's not sufficient and reported back to them. So I swapped over to the fibredine which does protect the RO much better and you don't have to change them so much either,  hence the RO should last 1 and a half to 2 years. I go through about 1500 to 2000 litres per week.
Hope it helps!
Cheers Chez

That's the problem Chez you think the Brodex is simply superb but at a tap tds of 280ppm there's no reason why you shouldn't get
your tds down to 3ppm.
Also a membrane should easily last 5 years before breaking down especially with such a low tap tds.
I certainly wouldn't class them as a superb system by any means.

 
Thanks for your opinion, which is all it is an opinion. I just gave mine that I'm am very happy with my system. ROs normally operate with a 5% margin, so as my tds tends to fluctuate between 280 and 320, and taking in to consideration water quality and water pressure, mine isn't particularly good, and as long as I get between 10 and 14 it's great. I've noticed many on here struggle to get the basic 5% efficiency, but mine consistently has from the day I bought it 5 years ago......happy days!
hi chez which membrane do you run?

Hey. I use the HF5 4040
Chez

Perfect Windows

  • Posts: 4123
Re: When to change RO Membrane
« Reply #23 on: September 26, 2014, 05:58:47 pm »
This is the issue which has been identified by Ian and his years of experience.

The chlorine block filter removes chlorine from the water as chlorine destroys membranes. Chlorine block filters only have a limited life.

The prefilters need to be replaced inline with the manufacturers directions.

Be careful on this: Some 20" prefilters have a suggested life of 22,000 litres, some as high as 75,000.

Something that might be better than the replaceable filters with their short lifecycle is to use a DI vessel full of acid-washed charcoal (http://www.gapswater.co.uk/acatalog/Activated-carbon--acid-washed---25-kg-2193.html#SID=251) for £120

I use a 35" DI vessel and get a year out of a fill (about a third of the £120 bag) filtering about 430,000 litres last year.  So that's about 11,000 litres per £, much cheaper than any 20" filter I've seen.  Between the DI and the RO I have a sediment filter in case any charcoal dust gets out of the charcoal - it's acid washed so very little dust seems to get out.  Comes out pretty much spotless after a year, as the charcoal also filters out sediment in the water as well as the chlorine.

Vin

Smudger

  • Posts: 13254
Re: When to change RO Membrane
« Reply #24 on: September 26, 2014, 06:16:42 pm »
spruce, do you boost your water pressure?

If does the resin bottle handle that high flow rate ok?

Darran
A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty.

www.oddbodscleaning.co.uk

SeanK

Re: When to change RO Membrane
« Reply #25 on: September 26, 2014, 08:29:33 pm »
I agree you should find out what the TDS is coming out of the RO but before the resin. Mine comes out about 14 with a tap tds at 280. If it is in the 30's then you really do have to get a new RO. But the main problem I see for you is that the prefilters aren't doing their job or not changing them enough which is knackering your RO too soon. I have a Brodex system which is simply superb. However when I bought it they only have one prefilter fitted which was either a sediment or a carbon. It's not sufficient and reported back to them. So I swapped over to the fibredine which does protect the RO much better and you don't have to change them so much either,  hence the RO should last 1 and a half to 2 years. I go through about 1500 to 2000 litres per week.
Hope it helps!
Cheers Chez

That's the problem Chez you think the Brodex is simply superb but at a tap tds of 280ppm there's no reason why you shouldn't get
your tds down to 3ppm.
Also a membrane should easily last 5 years before breaking down especially with such a low tap tds.
I certainly wouldn't class them as a superb system by any means.

 
Thanks for your opinion, which is all it is an opinion. I just gave mine that I'm am very happy with my system. ROs normally operate with a 5% margin, so as my tds tends to fluctuate between 280 and 320, and taking in to consideration water quality and water pressure, mine isn't particularly good, and as long as I get between 10 and 14 it's great. I've noticed many on here struggle to get the basic 5% efficiency, but mine consistently has from the day I bought it 5 years ago......happy days!

The expected lifespan of an 4040 membrane is 5 years with a 98% rejection rate that's the opinion of the manufacturers.

Spruce

  • Posts: 8366
Re: When to change RO Membrane
« Reply #26 on: September 26, 2014, 09:46:51 pm »
This is the issue which has been identified by Ian and his years of experience.

The chlorine block filter removes chlorine from the water as chlorine destroys membranes. Chlorine block filters only have a limited life.

The prefilters need to be replaced inline with the manufacturers directions.

Be careful on this: Some 20" prefilters have a suggested life of 22,000 litres, some as high as 75,000.

Something that might be better than the replaceable filters with their short lifecycle is to use a DI vessel full of acid-washed charcoal (http://www.gapswater.co.uk/acatalog/Activated-carbon--acid-washed---25-kg-2193.html#SID=251) for £120

I use a 35" DI vessel and get a year out of a fill (about a third of the £120 bag) filtering about 430,000 litres last year.  So that's about 11,000 litres per £, much cheaper than any 20" filter I've seen.  Between the DI and the RO I have a sediment filter in case any charcoal dust gets out of the charcoal - it's acid washed so very little dust seems to get out.  Comes out pretty much spotless after a year, as the charcoal also filters out sediment in the water as well as the chlorine.

Vin

Actually Vin I'm glad you posted on this thread as I was going to ask you if your Charcoal filter was working for you. You must have had it in for about 3 years by now.

The question is want to know is how you know when the charcoal is spent and needs to be changed.

At the moment we are using the 20" Fiberdyne chlorine block filters. We have to accept the manufactures tell us to change them when they have processed a certain amount of water (77,000 liters), but what happens if the water board use more than the 'normal' amount of chlorine in the water? I would imagine the carbon block filters won't last as long.
Success is 1% inspiration, 98% perspiration and 2% attention to detail!

The older I get, the better I was ;)

Perfect Windows

  • Posts: 4123
Re: When to change RO Membrane
« Reply #27 on: September 26, 2014, 10:08:25 pm »
Actually Vin I'm glad you posted on this thread as I was going to ask you if your Charcoal filter was working for you. You must have had it in for about 3 years by now.

The question is want to know is how you know when the charcoal is spent and needs to be changed.

At the moment we are using the 20" Fiberdyne chlorine block filters. We have to accept the manufactures tell us to change them when they have processed a certain amount of water (77,000 liters), but what happens if the water board use more than the 'normal' amount of chlorine in the water? I would imagine the carbon block filters won't last as long.

Bluntly, I don't know when the charcoal's spent.  I ran it and watched my RO output TDS like a hawk.  After about 13 months the TDS hadn't increased (so I assume no chlorine getting through) but I lost my bottle and changed the charcoal.

One of the main reasons I like it is just that I don't have to mess about with changing it more than once a year.  I'm all for an easy life.  The fact that it's cheaper is just a bonus.  It's easy to change as the old stuff goes into a plant border and the new stuff pours in like dry sand.

One thing to note is that if you do it, you're only meant to fill the DI to 2/3 full, rather less than you would with resin.

Vin

Spruce

  • Posts: 8366
Re: When to change RO Membrane
« Reply #28 on: September 26, 2014, 10:25:56 pm »
Actually Vin I'm glad you posted on this thread as I was going to ask you if your Charcoal filter was working for you. You must have had it in for about 3 years by now.

The question is want to know is how you know when the charcoal is spent and needs to be changed.

At the moment we are using the 20" Fiberdyne chlorine block filters. We have to accept the manufactures tell us to change them when they have processed a certain amount of water (77,000 liters), but what happens if the water board use more than the 'normal' amount of chlorine in the water? I would imagine the carbon block filters won't last as long.

Bluntly, I don't know when the charcoal's spent.  I ran it and watched my RO output TDS like a hawk.  After about 13 months the TDS hadn't increased (so I assume no chlorine getting through) but I lost my bottle and changed the charcoal. ;D

One of the main reasons I like it is just that I don't have to mess about with changing it more than once a year.  I'm all for an easy life.  The fact that it's cheaper is just a bonus.  It's easy to change as the old stuff goes into a plant border and the new stuff pours in like dry sand.

One thing to note is that if you do it, you're only meant to fill the DI to 2/3 full, rather less than you would with resin.

Vin

Interesting. Thanks for reply.
Success is 1% inspiration, 98% perspiration and 2% attention to detail!

The older I get, the better I was ;)

Spruce

  • Posts: 8366
Re: When to change RO Membrane
« Reply #29 on: September 26, 2014, 10:39:08 pm »
spruce, do you boost your water pressure?

If does the resin bottle handle that high flow rate ok?

Darran

Hi Darran.

No booster pump on my r/o. Tap psi is 40 and has been all summer. Pressure goes up a bit in winter, but I'm not sure how this is possible as I believe our water is gravity fed from the reservoir on the hill above us. adding a booster pump would increase the production rate but the 2 lpm of pure with the HF5 membrane is well sufficient for us.

Not sure what you mean by this - If does the resin bottle handle that high flow rate ok? although I think your post was probably for Vin.
Success is 1% inspiration, 98% perspiration and 2% attention to detail!

The older I get, the better I was ;)

Perfect Windows

  • Posts: 4123
Re: When to change RO Membrane
« Reply #30 on: September 27, 2014, 08:51:00 am »
spruce, do you boost your water pressure?

If does the resin bottle handle that high flow rate ok?

Darran

Hi Darran.

No booster pump on my r/o. Tap psi is 40 and has been all summer. Pressure goes up a bit in winter, but I'm not sure how this is possible as I believe our water is gravity fed from the reservoir on the hill above us. adding a booster pump would increase the production rate but the 2 lpm of pure with the HF5 membrane is well sufficient for us.

Not sure what you mean by this - If does the resin bottle handle that high flow rate ok? although I think your post was probably for Vin.

The DI vessel (spectrum) is rated for 150psi, but I don't know about the flow rate itself.  I use it with a Clarke booster, which gives 80psi and, judging by the lack of damage to my RO membrane, I guess it's all working fine.  My input flow rate is around 600-800L/hr.

Hope that helps,

Vin

Smudger

  • Posts: 13254
Re: When to change RO Membrane
« Reply #31 on: September 27, 2014, 10:20:52 am »
Yes sorry,

I've never used a di vessle before the RO so I wasn't sure if it could handle the higher flow rate, no reason why not of course !

I'm producing 4k ltrs of water every other day, so this looks to be a better option than 20 inch filters

Esp. I've killed my RO in around 18 months...😥

Darran
A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty.

www.oddbodscleaning.co.uk

Spruce

  • Posts: 8366
Re: When to change RO Membrane
« Reply #32 on: September 27, 2014, 05:36:31 pm »
Yes sorry,

I've never used a di vessle before the RO so I wasn't sure if it could handle the higher flow rate, no reason why not of course !

I'm producing 4k ltrs of water every other day, so this looks to be a better option than 20 inch filters

Esp. I've killed my RO in around 18 months...😥

Darran

Even with longer lasting carbon block filters you will be needing to change them every 7 - 10 days depending on you pure to waste ratio using that amount of water.

Success is 1% inspiration, 98% perspiration and 2% attention to detail!

The older I get, the better I was ;)

Smudger

  • Posts: 13254
Re: When to change RO Membrane
« Reply #33 on: September 27, 2014, 07:36:52 pm »
Yes depressing isn't it, however a di full of acid washed carbon sounds a good alternative

Darran
A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty.

www.oddbodscleaning.co.uk