check over my RO DI

[Jbone1228]

I use the RO/DI at work and in the holding tank TDS is reading 30’s. We have all new filters and DI. We use this water for our printing presses, just want someone to look over the plumbing. looks like a ton of waste water is going out.

 

[nereefpat]

I would test the TDS right out of the tap and make sure it is near zero. Stored water has a tendency to attract things that adds to a conductivity reading.

 

[steallife904]

Looks like a lot of dust on stuff. I wonder if the water storage barrel is dirty???

 

[Woodyman]

I use the RO/DI at work and in the holding tank TDS is reading 30’s. We have all new filters and DI. We use this water for our printing presses, just want someone to look over the plumbing. looks like a ton of waste water is going out.

I can't view the video, but if your concerned with waste water the best thing you could do currently is to add a booster pump. After that get higher quality RO membranes, a permeate pump/flush kit, and a high quality sediment and carbon prefilters.

Also if you require higher volume at work, you would be better off with a single bigger membrane. A 400GPD membrane doesn't take up a ton of space and would be better than 4 100GPD membranes.

 

[Jbone1228]

i didn’t set the ro up, the tap water here is like 40 in Kc.

 

[Jbone1228]

the tds isn’t a big deal for work but my aquarium yes ha

 

[Woodyman]

the tds isn’t a big deal for work but my aquarium yes ha

As mentioned before the storage container is more than likely responsible for the TDS increase in product water. Does the unit not have a TDS meter on the final output?

Remember TDS is relative as well, 30ppm TDS or straight Ca/Mg wouldn't be an overly big deal, however 30ppm TDS of silicates/phosphates would not be ideal even in small quantities. The TDS isn't as important as the makeup of the TDS, but without an ICP analysis you won't know how much to worry.

 

[Jbone1228]

It does have a tds meter, when i hit the button it blinks green. Yes the barrel is like 12 years old, never been flushed .

 

[Woodyman]

I would test the TDS right out of the tap and make sure it is near zero. Stored water has a tendency to attract things that adds to a conductivity reading.

Storage, along with the container! For example we bought a new ~60 gallon norwesco a few years back and the TDS from that (along with TOC) was high for ~9 months. At least higher than we wanted. 2 good cleans/sanitizing and plenty of rinsing and we finally got it down to acceptable levels, and that's also recycling the water through UV 24/7.

So your container will leach for several months even when it's designed for water storage.

 

[Woodyman]

It does have a tds meter, when i hit the button it blinks green. Yes the barrel is like 12 years old, never been flushed .

Probably could use a good clean/sanitizing. What style meter do you have and what is the setpoint? We have some online resistivity meters and it has color coded LEDs as well as an actual reading. Below the set point and it goes orange, below another setpoint and it goes red, but it also always displays a physical number. We aim for 18+ Mohm on the meter.

 

[Jbone1228]

here is a pic of our ultra meter, water out from the barrel.

 

[Woodyman]

here is a pic of our ultra meter, water out from the barrel.

What do you get as a reading exiting the DI?

 

[Jbone1228]

this is exiting DI

 

[Woodyman]

this is exiting DI

If that meter is properly calibrated, then your well overdue for a DI resin replacement.

 

[Woodyman]

How many stages of DI are present. I see a label on the sediment and 2 carbon filters. I don't see any with DI.

 

[Jbone1228]

just one stage di

 

[Woodyman]

just one stage di

Well it's time to change that stage out. I'd say it's recommended to at least do dual DI, especially if your aiming for pure water in an industrial setting.

 

[Jbone1228]

tester says low battery so ill get a new one in tomorrow. also my stepbrother just said he pried the old di filter apart and refilled it with resin is that ok?

 

[Woodyman]

tester says low battery so ill get a new one in tomorrow. also my stepbrother just said he pried the old di filter apart and refilled it with resin is that ok?

Batteries sometimes affect readings on analytical instruments. I'd replace the battery, verify calibration, and then get an accurate reading.

Yes you can refill DI canisters with fresh resin, but if they aren't properly packed the water will channel and bypass a majority of the resin. So you might go from say 1/2 TDS into the resin and 0 coming out to 1/2 going in and back out shortly after.

So as long as it's been properly packed it's not an issue to refill.

Another thing though when using bulk resin you need to ensure the original container the resin was purchased in is thoroughly sealed. Any air leakage will deplete the resin lowing the capacity when you eventually use it. Resin will absorb ions from the air just like it does in water, it's slower, but it still happens.

 

[Jbone1228]

ok ill be in touch tomorrow .