RO/DI Reading 10 TDS

[sstuckey]

I have a BRS 5 stage RO/DI unit with the set up to remove chloramines (because my city uses them).

 

I just replaced all cartridges including the RO/DI membrane in April. Last time I tested was around the end of May it was reading 0 TDS. Today its 10 TDS.

 

Please tell me I don't have to replace all the cartridges again already.

 

The DI resin hasn't gone gold. Maybe a little on the bottom. Is there a chance that I'd be good just getting new DI resin?

[Fluffeh]

sounds like u need to replace something.

i dont have an ro/di unit because i didn't want to spend all that money at once and i didn't want to deal with replacing or cleaning the extra stuff.

what i do is go to a local water place in town and get 75cents for 5 gallons. i tested the water with a TDS meter and its ALWAYS 002-004 TDS.

[sstuckey]

i tested the water with a TDS meter and its ALWAYS 002-004 TDS.

 

 

So how bad is 010?

[bensanders]

Not that bad. The problem comes from not knowing exactly what constitutes the 10 TDS.

[cactuspat]

see what tds you are getting from ro only, and then your supply water tds to determine how effective your membrane is working.

[sstuckey]

Not that bad. The problem comes from not knowing exactly what constitutes the 10 TDS.

 

 

Does it indicate the DI resin is spent?

 

see what tds you are getting from ro only, and then your supply water tds to determine how effective your membrane is working.

 

RO only 025

 

tap 213

 

I live in an old 1940 house with corroded pipes. Without RO there is a lot of rust in the water. My sediment filter is showing a slight orange to it.

[bensanders]

Does it indicate the DI resin is spent?

 

It might, what color is your resin as it stands now? Best way to tell would be to measure the TDS of the water going into the resin and then measure the water leaving the resin, compare the difference.

[cactuspat]

Pre filters should not change tds. What kind of membrane are you using cause the one you have is running at about 88% efficiency and should be higher i believe. You could always wait for AZ to chime in and he could help you troubleshoot your problem.

[sstuckey]

Pre filters should not change tds. What kind of membrane are you using cause the one you have is running at about 88% efficiency and should be higher i believe. You could always wait for AZ to chime in and he could help you troubleshoot your problem.

 

 

75 GPD Dow Filmtec RO Membrane

 

I'll check again when I get home on the pre resin reading. Make sure it wasn't the cup I was testing in.

 

It might, what color is your resin as it stands now? Best way to tell would be to measure the TDS of the water going into the resin and then measure the water leaving the resin, compare the difference.

 

It's a little gold near the bottom. I've seen worse.

[cactuspat]

That membrane should be 95%-98% effective so i would say u have a bad membrane which is wearing out your di resin too fast.

[sstuckey]

That membrane should be 95%-98% effective so i would say u have a bad membrane which is wearing out your di resin too fast.

 

 

DANG! that's the most expensive part. It's like going in for a new muffler and they tell you you need a catalytic converter.

 

I appreciate the help though.

[ColaAddict]

time to replace RO and DI. RO supposed to take out 98-99% of TDS, and the DI supposed to take out the last 1% to make 0TDS water. As said above a bad RO unit will exhaust the DI resin fast. The activated carbon and prefilter supposed to be good for 6 months. You don't know what's in that 10TDS that you are getting, could be phophate or something more dangerious. the chlorines/cholramines are taken out by your activatated charcoal filter, so as long as you replace every 6 months, you should be good. You might want to replace your pre-filter sooner than 6 months if your water is rusty or has alot of other solid stuff in it, so your RO doesn't get used up so fast. Pre-filters are cheaper than the RO unit.

[AZDesertRat]

A good RO membrane is a 98% efficient device so should take your tap water from 213 to 4 or 5 worst case.

The DI resin should then take that 4 or 5 down to 0 TDS for quite awhile unless you have entrained CO2 in your water which is possible.

 

A membrane should last 3+ years easily and with a high quality, low micron prefilter and single 0.5 micron 20,000 gallon carbon block could go 10 years or more. I am at 3.5 years on my current membrane with 650 TDS going in and still at 99.35% rejection rate so it is possible.

 

Forget the "chloramine" filters, you do not need nor want them. A single Matrikx +1 0.6 or 0.5 micron carbon block is more than sufficient for the chlorine portion of chloramines, its the DI resin you need to pay attention to as its the ammonia that is a killer with chloramines and the RO membrane is not particularly effective at removing all forms of ammonia.

When I get home later I can go into much more detail but sounds like you need a prefilter, carbon block, membrane and DI resin at this point. Don't order anything untile we can do a little more troubleshooting and I can suggest several much better products than you have been using that will give you better service and cost less in the long run.

 

In the meantime, get your water pressure, water temperature, actual measured waste ratio with a watch or clock and measuring cup and your tap water TDS, RO only TDS and final RO/DI TDS using a clean clear glass drinking water glass washed by hand in very hot water so no soap residue or hard water spots and triple rinsed in good distilled or RO/DI water between each reading for accuracy. All these have a great deal with how well things work.

[cactuspat]

There he is ^ It doesn't take long when your thread title has tds in it lol.

[sstuckey]

A good RO membrane is a 98% efficient device so should take your tap water from 213 to 4 or 5 worst case.

The DI resin should then take that 4 or 5 down to 0 TDS for quite awhile unless you have entrained CO2 in your water which is possible.

 

A membrane should last 3+ years easily and with a high quality, low micron prefilter and single 0.5 micron 20,000 gallon carbon block could go 10 years or more. I am at 3.5 years on my current membrane with 650 TDS going in and still at 99.35% rejection rate so it is possible.

 

Forget the "chloramine" filters, you do not need nor want them. A single Matrikx +1 0.6 or 0.5 micron carbon block is more than sufficient for the chlorine portion of chloramines, its the DI resin you need to pay attention to as its the ammonia that is a killer with chloramines and the RO membrane is not particularly effective at removing all forms of ammonia.

When I get home later I can go into much more detail but sounds like you need a prefilter, carbon block, membrane and DI resin at this point. Don't order anything untile we can do a little more troubleshooting and I can suggest several much better products than you have been using that will give you better service and cost less in the long run.

 

In the meantime, get your water pressure, water temperature, actual measured waste ratio with a watch or clock and measuring cup and your tap water TDS, RO only TDS and final RO/DI TDS using a clean clear glass drinking water glass washed by hand in very hot water so no soap residue or hard water spots and triple rinsed in good distilled or RO/DI water between each reading for accuracy. All these have a great deal with how well things work.

 

 

Sweet. Now we're talkin.

 

I'll take a look tonight. I don't have something to measure pressure. Everything else I can do.

[sstuckey]

Sorry guys...

 

False alarm. I just tested and made sure it was a clean glass, no spots, rinsed first with the RO/DI. Tested 0 just like a month ago.

 

My mistake. I tested last night in my top off jug which apparently isn't clean enough.

 

I apologize for my mistake, but I'll still take the suggestions on the replacement products for when needed AZDesertRat...

 

 

Incredibly dumb on my part and a bit over reacted. But I will never make that mistake again.

[AZDesertRat]

A pressure gauge and a TDS meter are the two most important things you can have with a RO or RO/DI system, its impossible to troubleshoot one without both of them. The next most important things are a measuring cup and a clock or wristwatch to measure the waste ratio which is critical to a membranes lifespan and performance.

Color changing resins are hit and miss, mostly miss, and guessing the waste ratio will often result in a toasted membrane.