is this possible?

[lr85ninety]

just fitted an RO MAN inline tds meter to my non sponser 3 stage ro unit (a very good make) and after an hour it is saying im producing RO at zero ppm now the best reading iv had with my tds pen is 6 ppm altough thats not running RO more like stored RO i thought zero ppm wasn't possible/highly unlikely with no di filter so are my readings right?

[Tetley]

Hi,

Zero is what you should be aiming for, as you have zero - :):):):):):)


HTH

Tets.

[lr85ninety]

yeah dont get me wrong im impressed just thought the lowest id get without a di filter would be 2 or 3 ppm

[Tangman]

Hi you have got it connected up right i assume, as if not it wont register right also it will need calibrating as well. HTH Twiggy

[lr85ninety]

yeah it connected right and followed the instructions it is working it starts at 300ppm at the mains side and within 10 mins running the output side is reading around 5ppm then after an hour or so it drops to zero!?

[Tangman]

yeah it connected right and followed the instructions it is working it starts at 300ppm at the mains side and within 10 mins running the output side is reading around 5ppm then after an hour or so it drops to zero!?
Hi is it a before and after one or just an inline one, has it got 2 readings on the lcd. Twiggy

[lr85ninety]

its a before and after one the mains side is measuring 300ppm

[Dal]

Shows how inaccurate TDS pens are IMO

I know someone else who gets Zero he has a 3 or 4 stage RO man unit
Happy Days I say:D

[lr85ninety]

well i tested the water as best i can coming out the outflow pipe with the pen something iv not done before as i thought it'd be inaccurate and even its reading 1ppm so i think i'l just count myself lucky lol!;)

[Tangman]

its a before and after one the mains side is measuring 300ppm
Hi well it looks like you have it fitted wrong ,as one end has to be fitted to where the water comes out of the membrane, and the other it connected to where the good water or di unit is that way you can see if your membrane is wanting replacing or when your DI is exhausted. HTH Twiggy:D PS you say the mains side is 300, this is no good as you need to know what it is after the membrane which is why it goes this way.

[moorish]

it seems very strange getting a zero reading so very quickly,my ro still reads 5 or6 coming out even after a couple of weeks.i have a deioniser on mine but unable to get the tds reading down to o.derek

[MR Teee]

RO membranes reject anything from 95-99% of solids, chances are if its 300TDS going in AND rejecting 99% then you would be getting 3TDS out. Aloowing for the error in the unit, its possible it could be reading zero.

As others have said though, whilst its good to know what the tds is going in, its also nice to know what percentage your membrane is rejecting (by placing the meter directly before and after the membrane).

Once you have a DI unit ( i highly recommend you to get one from RO-man) you should place the probes between the membrane and the DI and then the other after the DI pod.

With DI you should always be at zero TDS, if not then the DI resin has come to the end of its life.

[mad pierre]

Can someone advise what reading is acceptable between the membrane and DI unit? Also what sort of readings here would indicate the membrane needs replacing?

Peter

[MR Teee]

Depends on the input, as i said, less than 95% rejection and the membrane needs replacing.

At 300 TDS a reading over 15 TDS after the membrane would indicate that it needs replacing.

[mad pierre]

Depends on the input, as i said, less than 95% rejection and the membrane needs replacing.

At 300 TDS a reading over 15 TDS after the membrane would indicate that it needs replacing.

Cheers for that

Peter

[lr85ninety]

im stupid it would seem lol :)because i cant see the diffrence in where you place the meter the way i connected first gives the same reading as the way you guys have told me to connect it! im a little confused so the purpose of the carbon filter and micron filter are? surely i need to know there condition too. The moment my ppm's start to rise i know somethings at fault then change the membrane and filters as their cheap to ensure my ro unit are well serviced? cheers for this guys you are helping me! evfen if i must come across a little daft lol:D

[MR Teee]

nah dont worry about the prefilters, just change them every 6 -8 months regardless.

Their prupose is to remove big particles by the prefilter, and the carbon block to neutralise the chlorine. Neither have a major effect on the ppm reading.

[lr85ninety]

so surely the readings would be the same where ever you fit it? lol this is getting worse i know!

[Tangman]

im stupid it would seem lol :)because i cant see the diffrence in where you place the meter the way i connected first gives the same reading as the way you guys have told me to connect it! im a little confused so the purpose of the carbon filter and micron filter are? surely i need to know there condition too. The moment my ppm's start to rise i know somethings at fault then change the membrane and filters as their cheap to ensure my ro unit are well serviced? cheers for this guys you are helping me! evfen if i must come across a little daft lol:D
Hi m8 dont worry it baffled me when i first got mine until MR TEEE told me i was wrong, clever man is our BRAINS. Twiggy:D:D

[lr85ninety]

i think i need a lie down lol i hate stuff i dont understand or at least stuff i think i do but then find out i dont lol give me electrics and im fine but water hmmm just goes through pipes!

[toonfan]

well if it helps i also tested my r/o water when i first got my tds meter and it was just over 99 going in and 1 coming out but changed to 0 after about a week and 3 months later is still 0 - to be sure i took my r/o water to my local fish shop who confirmed it was infact zero - some people like you say are just lucky that they get a good water supply

[mikk1301]

i think i need a lie down lol i hate stuff i dont understand or at least stuff i think i do but then find out i dont lol give me electrics and im fine but water hmmm just goes through pipes!goes to show water and electrics dont mix;)