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Di resin problems

WinWiz

Member
Messages
56
As some of you know, I bought a Pure Freedom van fitted system a year ago. Recently, I've started having a consistent problem with the DI Resin. It only seems to last 2 weeks! I've had this problem now for 4 months. It's costing me a fortune! I really can't afford to change the resin every two weeks.

After 2 weeks, the water reading goes from between 0-2 all the way up to 12. Has anyone had this problem before? The RO produces 45 before it gets pushed through the DI Resin. I've tried asking the guys at Pure Freedom but they are stumped. Can anyone guide me?

 
If your are pushing 45 ppm through the di resin it's not going to last very long for sure.You should be looking at replacing the ro surely as at 45ppm output it seems fooked to me.

What size di tank do you have ?

Have a play on this to get a rough idea how long resin should last http://www.gardinerpolesystems.co.uk/Resin Calculator.htm

WOW!!! That's why I love this site!! That's a fantastic link!!

I put my stats in and it came out at two weeks! Which is exactly what's happening! /emoticons/smile.png

Thanks so much!!!! /emoticons/biggrin.png

I have a replacement RO at the ready. Will get cracking getting that swopped out now.

(Wall Tap TDS reading is 260 btw. I have a booster pump for the RO too. I buy the Ultratec RO unit and the Tulsion resin from Pure Freedom)

 
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I have no RO. Tap water is 60. I pump through two 11ltr DI's on demand. I use 2000 ltrs per week and resin lasts a min of 6 weeks before I change, allowing TDS to reach 002.

 
Nice one & I'm glad I have been some help :thumbsup:

WOW!!! That's why I love this site!! That's a fantastic link!!I put my stats in and it came out at two weeks! Which is exactly what's happening! /emoticons/smile.png

Thanks so much!!!! /emoticons/biggrin.png

I have a replacement RO at the ready. Will get cracking getting that swopped out now.

(Wall Tap TDS reading is 260 btw. I have a booster pump for the RO too. I buy the Ultratec RO unit and the Tulsion resin from Pure Freedom)
 
I'm a bit surprised to hear that Pure Freedom are stumped.

It sounds to me as though the membranes have seen better days as per Smurfs evaluation. Your r/o is only working to an efficiency of 83% with your tap tds and output after membranes but before di.

On most r/o's you should be runing at around 97 - 99%, meaning that your pure should be coming out at around 4 - 8 ppm.

If you have to replace membranes a good idea is to mark each pipe membrane housing with a pipe number, ie 1 to 9, with masking tap and then wrap a piece of masking tape around each pipe you remove and write the number on it. You will then be able to put it back exactly the way you took it apart. I've known cleaners get pipes mixed up and contaminating the pure by coupling a waste into it by mistake.

If you haven't been doing your maintenance properly, like replacing the prefilters, then it is likely that chlorine from your tap water has destroyed your membranes. Its very important that prefilters, especially the carbon block filter is replaced regularily according to water used.

If you have a typical RoMan type r/o then it is likely that the waste to pure ratio is 3 to 1. So for every litre of pure you produce you will use 4 litres of water from the tap. If you are using a Fiberdyne filter from Gardiners for example, a 10" filter will remove the chlorine from 37,000 litres of water. That's 9 x 1000 litre IBC tanks of pure water. If you use 400 litres per cleaning day, then you need to be replacing these filters every 23 working days - approx once a month.

In the early days our 450GPD would bring our tap water down from 254 to 4.

 
So how often should you change your membrane I've had mine in now 14months changed the pre filters once

At the moment using 800lts per day my resin is lasting 5weeks

 
So how often should you change your membrane I've had mine in now 14months changed the pre filters onceAt the moment using 800lts per day my resin is lasting 5weeks
My membrane is in it's 6th year come Jan mate :thumbsup:

 
So how often should you change your membrane I've had mine in now 14months changed the pre filters onceAt the moment using 800lts per day my resin is lasting 5weeks
When they stop performing. In my books I would change them once they get to around 94% efficiency. Anything after that you are putting off the inevitable.

Our last lot of 150 GPD membranes lasted 6 years. I bought that r/o when it was a year old. The membranes lasted me about 6 months as the previous owner didn't replace prefilters. We live in the same town with the same water supply.

Now we have 4040 and that is 2 1/2 years old - the membrane is producing water at 2ppm, exactly the same as it did when it was first commissioned.

Sediment filter get changed every 3 weeks and fiberdyne 20" carbon block about every 3 months when it has filtered 78000 liters of water. I have a water meter which counts the liters used and set off an alarm to advise when that filter needs changing.

 
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I'm a bit surprised to hear that Pure Freedom are stumped.
It sounds to me as though the membranes have seen better days as per Smurfs evaluation. Your r/o is only working to an efficiency of 83% with your tap tds and output after membranes but before di.

On most r/o's you should be runing at around 97 - 99%, meaning that your pure should be coming out at around 4 - 8 ppm.

If you have to replace membranes a good idea is to mark each pipe membrane housing with a pipe number, ie 1 to 9, with masking tap and then wrap a piece of masking tape around each pipe you remove and write the number on it. You will then be able to put it back exactly the way you took it apart. I've known cleaners get pipes mixed up and contaminating the pure by coupling a waste into it by mistake.

If you haven't been doing your maintenance properly, like replacing the prefilters, then it is likely that chlorine from your tap water has destroyed your membranes. Its very important that prefilters, especially the carbon block filter is replaced regularily according to water used.

If you have a typical RoMan type r/o then it is likely that the waste to pure ratio is 3 to 1. So for every litre of pure you produce you will use 4 litres of water from the tap. If you are using a Fiberdyne filter from Gardiners for example, a 10" filter will remove the chlorine from 37,000 litres of water. That's 9 x 1000 litre IBC tanks of pure water. If you use 400 litres per cleaning day, then you need to be replacing these filters every 23 working days - approx once a month.

In the early days our 450GPD would bring our tap water down from 254 to 4.

Thanks Spruce. Your knowledge is impressive. Maybe PureFreedom were not stumped. Simply unhelpful. I got nowhere near this type of help from them. They are either disinterested, too busy or weary because they gave me a 1 year warrentee and the RO stopped working well before the year was up.

Because I use 2000 liters a week, I'm using 8000 liters from the tap.

So what you're saying is, if I was to look at system maintenance in it's entirety:

I'm on the South Coast - south of the Downs. Chalky water. So I top-up the salt for the softner every week.

In addition to that, I should:

- Change the two pre-filters every 3 months

- Flush the RO for two hours once a week

- Flush the RO twice a week for 15 min

- Change the RO when the PPM goes over 8

- Change the DI Resin when the PPM goes over 10

Does that sound good?

 
I tend not to use pure it goes above 000ppm myself. You could put another di tank inline to get the most out of the resin if you wanted. Twin di method is what I'm now using after the ro as I'm a tight **** when it comes to shelling out on resin.

 

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