RO/DI water - TDS meter = 6

[Playdope]

I've made 3 testing attempts to be sure... since the last post. Always 3 ppm both before and after DI... weird.

The water before purifying is about two twenty something.. dont remember for sure.

Jon

 

[Ben1]

was your TDS meter calibrated?

 

[Playdope]

I've looked on the meter, and i dont see anywhere to calibrate it. If you have seen this meter, and know how to calibrate it.. let me know:

http://www.binaryillusions.com/adrian/p ... 8/DSC01146

 

[Anonymous]

You need to confirm the meter by taking reading of sample with known TDS reading. IMHExperience, majority of these handheld meter used in the hobby works fine for tap and RO, but not very good for ultrapure water like RO/DI.

 

[Anonymous]

There is a solution that you use to calibrate and 0 out the meter.
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[Playdope]

Did you look at the picture? Are you certain it is the one in the pic that could be calibrated?

If so... where?

 

[Anonymous]

Some may have a screw ("pot") inside a hole on the back for you to adjust, but I doubt that this will solve you problem. Most hobby TDS meter, if calibrate-able, only let you change the slope of the reading. There is not much you can do if it don't do well in the intercept aspect (zero). What I think you should do is to verify that it is working the way it should by using a sample with known TDS (calibration fluid, for example). Once you know your meter is actuate for sample between "0" ppm and 5 ppm, for example you can be confident in calling up the resin people and tell them their filter do crap.

Keep in mind that another issue with DI filter is that you need to make sure the water have sufficient contact time with the resin for it to work well. You can't just push 5 gal of water thru the filter in one minute and expect it to drop the ppm down to almost nothing.

 

[SCIronMike]

Very strange that your Filter Direct unit with just RO is putting out water with 20 ppm, and mine before DI is putting out 3 ppm?!? Very very weird. How are you feeding your unit? You wouldn't by chance have yours connected to a faucet adapter?

Also, are you using one of those handheld beige TDS meters from filter direct?

Jon

Yes, it is the handheld TDS meter from Filter Direct. The feed line to my RO/DI unit is hooked through a hose adapter to the laundry room cold water line.

 

[Playdope]

Do you know the model DI filter you have? I am curious to know if we have the same one. :/

 

[SCIronMike]

Do you know the model DI filter you have? I am curious to know if we have the same one. :/

No idea. I thought all their DI filters were the same? It's just a plastic container in which you add DI resin.

 

[Playdope]

No clue, i guess the next step is to call them