What is going on with my TDS?

[spruce]

Right I've been able to measure my timings. Here's the results:

Water from tap - 410ppm (I know I cry)

RO - Bringing it down to 31ppm

Time to fill 1L of pure - 22 secs

Time to fill 1L of waste - 9 secs

Pressure - 50psi.

Any ideas @spruce @doug atkinson

I'm not sure I should be getting involved. My brain reversed polarity this morning and hasn't worked properly today at all.

Let my brain figure this out slowly. You are getting a ratio of 70% waste to 30% pure (6.6 liters of waste per minute to 2.7 liters of pure per minute. You are using 9lpm of water which imo is too much.

At 50psi my 4040 does fractionally under 2lpm of pure and just over 2lpm of waste per minute. I would try reducing your waste a bit more. 

I think @doug atkinson is better qualified by a long way to help you.

 

[Pjj]

I'm not sure I should be getting involved. My brain reversed polarity this morning and hasn't worked properly today at all.

Let my brain figure this out slowly. You are getting a ratio of 70% waste to 30% pure (6.6 liters of waste per minute to 2.7 liters of pure per minute. You are using 9lpm of water which imo is too much.

At 50psi my 4040 does fractionally under 2lpm of pure and just over 2lpm of waste per minute. I would try reducing your waste a bit more. 

I think @doug atkinson is better qualified by a long way to help you.

Lol you are doing better than me I couldn’t even try and work that out mathematically ????

 

[Suhrly]

I'm not sure I should be getting involved. My brain reversed polarity this morning and hasn't worked properly today at all.

Let my brain figure this out slowly. You are getting a ratio of 70% waste to 30% pure (6.6 liters of waste per minute to 2.7 liters of pure per minute. You are using 9lpm of water which imo is too much.

At 50psi my 4040 does fractionally under 2lpm of pure and just over 2lpm of waste per minute. I would try reducing your waste a bit more. 

I think @doug atkinson is better qualified by a long way to help you.

Thanks @spruce I appreciate every second of your time. By the way your brain working at 60% is still better than mine working at 100% ?

 

[con95a]

So after a few days using my 4040, flushing before and after for a couple of minutes, the efficiency has slowly risen. On average now I'm getting 93%-93.5%

So hoping that will keep rising until I get about 95%-96%

(Although I don't know how trustworthy the inline TDS meter is (HM Digital DM-2) as I put both sensors one after the other on the supply feed and they were 10-12ppm different from each other. Which could be giving false efficiency calculation. So looks like I'll have to calibrate them for peace of mind)

Have you seen any improvement @Suhrly

 

[Jango]

The inline TDS one sensor goes before Di then one goes after Di. 
so for me I have a TDS reading of 11 going in and because I’ve just changed my resin I have a TDS coming out of Di vessel going into ibc tank of 0 TDS. 
im not sure what efficiency this gives me@spruce 

so are your probes in correct places? 

 

[Part Timer]

The inline TDS one sensor goes before Di then one goes after Di. 
so for me I have a TDS reading of 11 going in and because I’ve just changed my resin I have a TDS coming out of Di vessel going into ibc tank of 0 TDS. 
im not sure what efficiency this gives me@spruce 

so are your probes in correct places? 

Depends on what the TDS from your tap is, as long as it's above 275 your membrane is removing at least 96% of the impurities

 

[Jango]

Depends on what the TDS from your tap is, as long as it's above 275 your membrane is removing at least 96% of the impurities

My Tap TDS is 284

 

[Part Timer]

My Tap TDS is 284

96.13% to be exact ?

 

[Jango]

96.13% to be exact ?

 Nice one. Thank you, it’s 3 years old now the membrane, but I really look after my pre- filters etc. So all is good. 

 

[doug atkinson]

So after a few days using my 4040, flushing before and after for a couple of minutes, the efficiency has slowly risen. On average now I'm getting 93%-93.5%

So hoping that will keep rising until I get about 95%-96%

(Although I don't know how trustworthy the inline TDS meter is (HM Digital DM-2) as I put both sensors one after the other on the supply feed and they were 10-12ppm different from each other. Which could be giving false efficiency calculation. So looks like I'll have to calibrate them for peace of mind)

Have you seen any improvement @Suhrly

If your probes are not seated the right way it will give incorrect readings

 

[con95a]

The inline TDS one sensor goes before Di then one goes after Di. 
so for me I have a TDS reading of 11 going in and because I’ve just changed my resin I have a TDS coming out of Di vessel going into ibc tank of 0 TDS. 
im not sure what efficiency this gives me@spruce 

so are your probes in correct places? 

Yes that's how I usually have them, to check TDS after RO and then after resin. But I was suspicious of the readings so I put them both on the supply tube to see if they agree on my tap TDS, but they differed by about 10-12PPM

If your probes are not seated the right way it will give incorrect readings

I did double check this, the diagram on user manual shows they need to be both showing when looking down the T piece (perpendicular to flow I think?) 

Does it make sense for supply/tap TDS to increase slightly when closing gate valve? It seems to increase gradually as I gradually close the gate

 

[doug atkinson]

If you start reducing your waste less that 55% then your TDS will increase. It will also cause damage to your membrane if your reduce less than 50%.

 

[Suhrly]

So after a few days using my 4040, flushing before and after for a couple of minutes, the efficiency has slowly risen. On average now I'm getting 93%-93.5%

So hoping that will keep rising until I get about 95%-96%

(Although I don't know how trustworthy the inline TDS meter is (HM Digital DM-2) as I put both sensors one after the other on the supply feed and they were 10-12ppm different from each other. Which could be giving false efficiency calculation. So looks like I'll have to calibrate them for peace of mind)

Have you seen any improvement @Suhrly

To be honest I don't know as I was filling my tank right before I went to bed with a 'fuq it' attitude. When I checked in the morning it was hitting my DI at 7ppm (which I was happy with) but my tap TDS fluctuates WILDLY. I mean one minute it can be 300+, the next it's 65ppm. No joke. I've rang my waterboard to ask what is going on regarding TDS but they literally had no idea what I was even talking about. I've noticed when it doesn't rain for an extended period of time my TDS creeps up. I'll see what next week brings. Glad you're seeing better results. Now I'm starting to thing maybe my inline TDS meter is maybe off ??

 

[spruce]

To be honest I don't know as I was filling my tank right before I went to bed with a 'fuq it' attitude. When I checked in the morning it was hitting my DI at 7ppm (which I was happy with) but my tap TDS fluctuates WILDLY. I mean one minute it can be 300+, the next it's 65ppm. No joke. I've rang my waterboard to ask what is going on regarding TDS but they literally had no idea what I was even talking about. I've noticed when it doesn't rain for an extended period of time my TDS creeps up. I'll see what next week brings. Glad you're seeing better results. Now I'm starting to thing maybe my inline TDS meter is maybe off ??

Maybe its your TDS meter that's throwing these spurious readings.

 

[Suhrly]

Maybe its your TDS meter that's throwing these spurious readings.

Maybe it is mate got me thinking now. I have a Pure Freedom van system so it's one of those inline ones.

 

[Part Timer]

Maybe it is mate got me thinking now. I have a Pure Freedom van system so it's one of those inline ones.

Mine works, only difference from inline to a hand held meter is 1

 

[Suhrly]

Mine works, only difference from inline to a hand held meter is 1

Yeah think I'm gonna compare mine

 

[Baldmonkey]

Am I being dumb (quite a possibility) but did I read somewhere that your not supposed to close the waste tap when producing, which I don't, but a few have said in this thread they do... Am I reading this wrong? Confused 

 

[con95a]

Am I being dumb (quite a possibility) but did I read somewhere that your not supposed to close the waste tap when producing, which I don't, but a few have said in this thread they do... Am I reading this wrong? Confused 

Not completely closed, but needs to be closed so that it's fully open. By saying close the gap they mean enough to restrict flow but not stop it ??

 

[Suhrly]

So...the plot thickens. I've started to fill my tank for tomorrow. The TDS out of the tap is saying 330ppm approx (I say approx as it varies by the second it seems). The inline TDS meter in my van is saying the RO is bringing it down to around 20-21ppm. However I tested it with my handheld meter and that's reading 9ppm coming out of the RO! Which is much more satisfactory - if it's correct! So now the quandary is is my handheld or Inline meter off? ?‍

 

[Part Timer]

So...the plot thickens. I've started to fill my tank for tomorrow. The TDS out of the tap is saying 330ppm approx (I say approx as it varies by the second it seems). The inline TDS meter in my van is saying the RO is bringing it down to around 20-21ppm. However I tested it with my handheld meter and that's reading 9ppm coming out of the RO! Which is much more satisfactory - if it's correct! So now the quandary is is my handheld or Inline meter off? ?‍

Would think the inline is more likely to be wrong, no fellow windies nearby you can take a sample to? What's the inline saying going into the tank.