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sudden increase in PPM

tmcmahon92

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Messages
5
Location
worksop
my filters have been working fine for a while now, tds out of the Ro was about 20 which is a bit higher then id like but with resin always came down to 0 for 3000l at least.... anyway the filters were stored at my brothers for a week (on its side not sure if thats an issue) ... since then I have re-plumbed everything and suddenly the tds out of the ro is 135! I have no idea whats happening and assumed an issue with the waste filter but its not... I honestly have no idea whats happened! I assume i set everything up again... simple diagram any suggestion would be greatly appreciated!

RO.png

 
Many if us use the r/o in both the vertical and horizontal position @tmcmahon92

If the frost got the r/o then the membrane is damaged.

There should be no issue storing the housing for that short period provided it remains full of water. If the water was drained out or drained out by itself, it could have dried out depending on how and where it was stored.

You could also have a bacteria issue.

You don't say what your tap water input tds is. Knowing that would help us to decide how efficiently your membrane was working before.

If the membrane is old I would replace the lot tbh. I would also bleach all the housings and pipes to ensure you have no bug in the system destroying your membranes. Its usually evident in a buildup of slim in the membrane housing and on the membrane.

A new membrane should be removing between 97% and 98% of your water's total dissolved solids. Its generally accepted that once the figure drops to 94% its time to change the membrane.

My HF5 Axeon membrane is 6 years old and still working at a 97% rejection rate, down form 98% when it was new.

 
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Thanks for your help guys, tap water was running at 350ppm and always came down to around 20ppm so looks like it was perhaps time to change membrane soon anyway. just seems very odd to have jumped suddenly up to 100+ 

I have flushed the whole system thoroughly, even leaving it overnight. exactly the same result. 

my filters are around the same age as yours and have had relatively light use (4/5000l per month) for the first 4 years

I have Axeon housing and membrane also, looking at the childish diagram above does the plumbing look correct to you, I am doubting myself in everything now as it has gone bad so quickly, I guess the other option is bacteria of some form, I guess there is no way to rescue the membrane if that is the case?

 
Did you let it run for a few minutes before testing? In good condition I think you should be able to do much better than 20.

 
Thanks for your help guys, tap water was running at 350ppm and always came down to around 20ppm so looks like it was perhaps time to change membrane soon anyway. just seems very odd to have jumped suddenly up to 100+ 

I have flushed the whole system thoroughly, even leaving it overnight. exactly the same result. 

my filters are around the same age as yours and have had relatively light use (4/5000l per month) for the first 4 years

I have Axeon housing and membrane also, looking at the childish diagram above does the plumbing look correct to you, I am doubting myself in everything now as it has gone bad so quickly, I guess the other option is bacteria of some form, I guess there is no way to rescue the membrane if that is the case?


The tds of your pure at 350ppm should be between 7 and 11ppm and at worst 21ppm. 21ppm is usually the sign to replace membranes due to the cost of resin to polish that off.

Coupling the r/o up is simple. The inlet from the prefilters goes to the housing end where there is only 1 port. That's the feed end. On the other side of the r/o housing there's an end cap with two ports. The very center port is the pure and the port to the side is the waste.

It is always worth a try to pop the end cap from the feed end (the end with only one port)  and remove the membrane and check the seals. Check the brine seal on the membrane that its seating in the housing properly. Its the big seal you see first when removing the membrane from the housing. Dry it off and put a smear of silicon grease on all the seals. Return the membrane into the  housing with the black brine seal at the feed end (ie feed the membrane in with the brine seal end going in last).  Push the membrane firmly to ensure it is fully inserted.  Push in the end cap, again ensure it is fully inserted.

 
in that case what would you guys advise as a replacement RO Membrane... funds are a bit tight at the moment so the more budget friendly the better even if it means they will last a year or two less.

 
in that case what would you guys advise as a replacement RO Membrane... funds are a bit tight at the moment so the more budget friendly the better even if it means they will last a year or two less.


When it comes to buying membranes funds are always going to be tight.

There are cheap membranes available of Chinese origin. They are poor quality for not that much less money. What you might save in initial purchase cost will be made up many fold over with increased resin use. For example there is a membrane being sold by a company near you. The specs supplied by the manufacturer are a direct copy of the specs of a quality USA manufactured membrane. In reality the actual performance of that membrane is way below what the manufacturer advertises.

Be careful when buying membranes. There are a couple of suppliers that will advertise Axeon membrane but there is a note that they will supply either Axeon or Spectrum membranes to complete the order. What that means is that you will get a Spectrum membrane every time. Spectrum membranes aren't the same quality impo.

Another supplier used to sell Spectrum membranes but doesn't any more due to quality and performance issues.

Probably best to find someone who will sell you water until funds become less tight.

 
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