[C-N-C]

Hiya fellas,
Gunna make this short....probaly seen to much ov me latley....
anyway started ro up this morning,outside temp 4 deg-inside were ro is 6 deg
water going in RO in 511ppm when first turned on then drops to 322
water coming out  RO 50 (ish)

Normaly my merlin takes my water to 30 (ish)
so iv bin thinking all day........temp in shed never dropped below 3 deg
Now iv put heater next to RO on HOT the tds has gone back down to 30(ish) again.....EH.......
So the heat on my ro takes ppm down.........

Is that right??
must b using loads resin at that tds in winter...
Kindest regards
Justin

[Sapphire Window Cleaning]

Its the filteration system that filters the water. it works best in warmer weather yes.
the water temperature doesn't charge the TDS as the particals are still there whether the water is hot or cold.



Matt

[Sapphire Window Cleaning]

Your welcome mate.
What RO have you got?



Matt

[C-N-C]

Hiya man...
Merlin dude....
probaly better gettin summit bit better.....wonder if theres a RO designed for hards water areas....HMMMMMMM

Take care matt

Justin

[michael papworth]

A TDS meter works by measuring the electrical conductivity of a sample of water. The higher the level of tds, the higher the conductivity. It is ions that cause the conductivity.

That's why the meter has the two metal pins that go into the water. There's a voltage across them.

When a salt, calcium carbonate, for example, is dissolved in water, it ceases to be a solid, and splits into ions. In this case, it's ions of calcium (+ve charge) and ions of carbonate (-ve charge). There is an equal number of these +ve and -ve ions, so there is no net electrical charge in the water - you won't get a shock if you stick your finger into it. These ions just move around at random in the water so there is no net current flow - you can't get electrical energy out of it as it is. However, the ions are capable of conducting electricity. The more ions there are, ther greater the tds and the greater the conductivity. It's this conductivity that the tds meter measures.

Conductivity is also affected by temperature. I'm not absolutely certain about this, but I think it's got something to do with the higher mobility of the ions through the water when it is warmer and therefore less viscous - i.e. thinner.

So Matt is right that the temperature doesn't affect the tds as the particles (ions) are still there. But it DOES affect the readings on your meter.

It's important to realise that these meters aren't terribly accurate - particularly in the higher readings. Conductivity depends on the "size" of the ions, tds depends on the concentration of the ions. The two things are not related by a one-to-one correspondence. So tds meters are only accurate to about +/- 10% at a given temperature.

And I seem to recall that they are calibrated at a particular temperature.

RO units work better at higher temperatures due to the water being less viscous when it's warmer.

So there are two things to consider.

[dd]

Hiya man...
Merlin dude....
probaly better gettin summit bit better.....wonder if theres a RO designed for hards water areas....HMMMMMMM

Take care matt

Justin

To prolong he life of your membranes you would need a water softener. Not sure if it would improve tds much though.

[C-N-C]

Hiya wally mate...
Good post man,got most ov it ,but have to go throught rest morrow,verry techno   im bit thick
so that reading i got down to 30ppm might be wrong? could just be the wrong reading of meter because water etc warn (ish)
Why do you think my tds has risen?could be a number of things realy,couldnt it..... :
Thank you so much for your help wally

Hiya dd man..
Was thinkin of gettin 1,but my membrains just bin changed after bout 3 year of use...think they lasted okay....
Besides we thinking about moving so ill wait to c wot pans out

Thank you for ya help fellas

Take care & kindest regards

Justin

[C-N-C]

I think if you slow the flow of water to the RO that will bring down your TDS a bit more.

Hiya Ewan mate,
Ye might b right mate,it does deffo bring tds up lower psi.........
Im sure my booster took it to 80psi.... now its 70 psi....HMMMMMM......

Gunna think bout that 1 mate
Might be cold water harder to get through membrains
But intresting whot wally & matt and the other guys were saying

Anyway thanks man
Take care Ewan
Justin

[Jeff Brimble]

Put a restrictor/tap on your outlet pipe.

[ccmids]

cnc can you wrap some lagging round the RO that should help , thats what ive done

[dd]

I think if you slow the flow of water to the RO that will bring down your TDS a bit more.

Would think that would have the opposite effect Ewan.

[luther1]

I think if you slow the flow of water to the RO that will bring down your TDS a bit more.

Would think that would have the opposite effect Ewan.

Higher pressure,lower TDS.

[dd]

Ewan, the higher the pressure the better the membrane performs in bringing down the tds and producing the water more quickly.

Speed of production is not an issue for me as I use a static system, but I do know that the higher the pressure the purer the water.

Unless the pressure is excessive (above the max the membrane is designed to take without breaking up), there is no reason whatsoever to reduce it.

[dd]

What I meant Ewan is that membranes will be damaged if you exceed the pressure they are designed to withstand, around 120psi I think generally. Water pressure is not usually that high, but that is the only reason you need to reduce pressure.

I really think you don't know what you are talking about in this instance, and I really think i should stop posting on this now and possibly get a life.

[C-N-C]

Hiya EVERYONE...
Thanks for ya posts guy's
My merin NEEDS 40psi to even work.....the higher the psi the lower the tds......dat iz right guy's
i'v also Put a restricker tap on inlet....well 3 way tap...i turn tap to go to drain when i fist start ro up...then when the tds drops after a few mins i turn tap to close drain tap then open other wich goes to di then tank....
So the hight tds of tap water goes in drain for the fist few minutes until psi rises to 70psi then tds drops & then i turn tap to send nice water into ibc
Tried sediment & carbon filters b4 mate,just slowed psi down to RO.....resulted in higher tds man :
Well big "THANK YOU"  Ewan,Jeff Brimble ,ccmids ,dd ,luther1 ....for taking the time out to post    just finishedwith vans and system etc.....i started all this work friday night after collecting
Not just about window cleaning these reach & wash systems....LOL

Anyway guy's...just changed membrains not long ago...but gunna go buy a pre-filter for merlin........MAYBEE....just maybee..... could be due a new 1 ,carnt remember how long ago i exchanged it,
Iv been playing around ALL weekend ,changing resin,putting 3way tap on ro etc,also stuff in vans...PHEW!!!!! ...no wonder missus on me case....stuck in all weekend with 4 kids....

Well let ya all know if tds drops when i replace pre-filter morrow..
TDS still coming out of RO @ 40-50ppm-------before cold weather use to be 25-35ppm & psi bit lower now from 80psi to 70 psi
Take care all & kindest regards
YA SOUND GUY'S
Justin
www.clean-n-clearwindows.co.uk