Do i need to change membrane??

[Wayne33]

Hi Guys

Just done a system flush on my Purefreedom set up and i was getting 20ppm tds going into the tank after going through the resin.

Ive just done a check and im getting 30 ppm tds after the membrane before going through the resin and still 20 ppm after the resin?.

Does this mean i need to change the membrane?. I changed around 75% of the resin for new around 2 weeks ago and had to put a little 

of the old back in to top it up and both pre filters were changed around 6 months ago.

Thanks in advance.

Regards Wayne

 

[ks789]

Hi Guys

Just done a system flush on my Purefreedom set up and i was getting 20ppm tds going into the tank after going through the resin.

Ive just done a check and im getting 30 ppm tds after the membrane before going through the resin and still 20 ppm after the resin?.

Does this mean i need to change the membrane?. I changed around 75% of the resin for new around 2 weeks ago and had to put a little 

of the old back in to top it up and both pre filters were changed around 6 months ago.

Thanks in advance.

Regards Wayne

From what ive read on here and what the companies recommend you maybe should've changed the filters long ago. Especially if you've been producing a lot. 10,000 or so of pure is sometimes enough, especially if your in very hard water area. Filters are cheaper so try them first and keep a tab on how much goes through them. If filters arent good it will mess the membrane which is more costly, and also use up your di resin quicker ultimately

 

[spruce]

Hi Guys

Just done a system flush on my Purefreedom set up and i was getting 20ppm tds going into the tank after going through the resin.

Ive just done a check and im getting 30 ppm tds after the membrane before going through the resin and still 20 ppm after the resin?.

Does this mean i need to change the membrane?. I changed around 75% of the resin for new around 2 weeks ago and had to put a little 

of the old back in to top it up and both pre filters were changed around 6 months ago.

Thanks in advance.

Regards Wayne

Probably yes. You need to give us your input tds as well.

You also probably need to replace prefilters more often. When the service life of the carbon filter is used up then it lets water with chlorine into the membrane housing. Chlorine destroys membranes.You also need to replace all your resin, not just a bit and top it up with used.

An efficient membrane should remove about 98% of the dissolved solids in the water. So at a tap water tds of 100ppm the pure output should be 2ppm. The common rule of thumb is to replace the membrane when it gets to 94% efficiency, hence at a tds of 6ppm.

You can then apply your reading and work out where you are using the example.

So if you have an input tds of 250 and your output tds is 30 from your r/o we work out its efficiency the following way.

250 minus 30 = 220.

220 divide by 250 = 0.88

0.88 multiplied by 100 = 88% efficient

At 98% efficient your output tds would be 5

250 multiplied by .98 = 245. 250 - 245 = 5

.

 

[Wayne33]

Probably yes. You need to give us your input tds as well.

You also probably need to replace prefilters more often. When the service life of the carbon filter is used up then it lets water with chlorine into the membrane housing. Chlorine destroys membranes.You also need to replace all your resin, not just a bit and top it up with used.

An efficient membrane should remove about 98% of the dissolved solids in the water. So at a tap water tds of 100ppm the pure output should be 2ppm. The common rule of thumb is to replace the membrane when it gets to 94% efficiency, hence at a tds of 6ppm.

You can then apply your reading and work out where you are using the example.

So if you have an input tds of 250 and your output tds is 30 from your r/o we work out its efficiency the following way.

250 minus 30 = 220.

220 divide by 250 = 0.88

0.88 multiplied by 100 = 88% efficient

At 98% efficient your output tds would be 5

250 multiplied by .98 = 245. 250 - 245 = 5

.

Hi Spruce. 

Thank for the great info once again.

My ppm from the tap is 275 ppm. 

Im thinking maybe ill change the 2 pre filters again as they're only £23.

You are probably correct that ive not been changing frequently enough, as ive only been going around

7/8 months im still learning.

My system is a 650 ltr Purefreedom setup pic attached just in case. 

Thanks for the info again Spruce you were a great help when i asked some questions and the start and very

Knowledgeable.

A 40" membrane from Purefreedom is £197, is this the one to go for or is there any other options that are better?

Regards Wayne.

 

[Part Timer]

I have that system and use approx. 2000l a week, my tap TDS varies from 320 to 400+. My TDS after R/O is currently between 6 & 8. My membrane is 9 months old so are my pre filters, about to change them. How often do you flush?

 

[spruce]

Hi Spruce. 

Thank for the great info once again.

My ppm from the tap is 275 ppm. 

Im thinking maybe ill change the 2 pre filters again as they're only £23.

You are probably correct that ive not been changing frequently enough, as ive only been going around

7/8 months im still learning.

My system is a 650 ltr Purefreedom setup pic attached just in case. 

Thanks for the info again Spruce you were a great help when i asked some questions and the start and very

Knowledgeable.

A 40" membrane from Purefreedom is £197, is this the one to go for or is there any other options that are better?

Regards Wayne.

View attachment 11515

I'm old and cynical but this is from PF 4040 membrane page

http://purefreedom.co.uk/product/ro-ultratec-40-hf4-reverse-osmosis-membranes/

Please note, we have a varying stock of different brands of membrane. The one you receive may vary from the photo. If you would like to know what we have in stock at the moment please call us on 03331234365.

I seem to recall a few windies received a black coloured resin which PF said was Tulsion from America. Another supplier said it wasn't Tulsion resin at all. I like the PF product but this note concerns me. Order this membrane and you might get something else.

I would tend to look elsewhere. But that's my opinion.

Axeon are a good quality membrane. You have a booster pump so an HF4 should suffice.

http://www.gapswater.co.uk/acatalog/HF4-4040-Extra-Low-Pressure-Membrane-5216.html#SID=182

I wonder what membrane PF supplied with your system?

There are some really cheap and nasty 4040 Chinese manufactured membranes on the market. You have to stay well way from them.

.

 

[Wayne33]

I have that system and use approx. 2000l a week, my tap TDS varies from 320 to 400+. My TDS after R/O is currently between 6 & 8. My membrane is 9 months old so are my pre filters, about to change them. How often do you flush?

Hi Part Timer.

In all honesty ive only recently found out i had to flush a couple of times a week so i probably reduced the life of my pre filters.

I replaced them around 5/6 months ago and did the resin at the same time but i now know to keep on top of it.

Regards

 

[Wayne33]

I'm old and cynical but this is from PF 4040 membrane page

http://purefreedom.co.uk/product/ro-ultratec-40-hf4-reverse-osmosis-membranes/

Please note, we have a varying stock of different brands of membrane. The one you receive may vary from the photo. If you would like to know what we have in stock at the moment please call us on 03331234365.

I seem to recall a few windies received a black coloured resin which PF said was Tulsion from America. Another supplier said it wasn't Tulsion resin at all. I like the PF product but this note concerns me. Order this membrane and you might get something else.

I would tend to look elsewhere. But that's my opinion.

Axeon are a good quality membrane. You have a booster pump so an HF4 should suffice.

http://www.gapswater.co.uk/acatalog/HF4-4040-Extra-Low-Pressure-Membrane-5216.html#SID=182

I wonder what membrane PF supplied with your system?

There are some really cheap and nasty 4040 Chinese manufactured membranes on the market. You have to stay well way from them.

.

Hi Spruce.

Thanks agian for the help.

I never actually use the booster pump i just set the controller to 99psi and it probably takes around 4 hours to fill?.

Should i be using the pump?

Am i correct in assuming that the 40" Membranes and a universal fit and i can just buy them from anywhere?

Regards

 

[Part Timer]

Hi Part Timer.

In all honesty ive only recently found out i had to flush a couple of times a week so i probably reduced the life of my pre filters.

I replaced them around 5/6 months ago and did the resin at the same time but i now know to keep on top of it.

Regards

Your preserve the membrane by flushing not the pre filters.