Another DI color change resin thread

[DanConnor]

Since so many people here like to trouble-shoot RO systems...

I was amazed to see much people said are getting out of their DI resin in the other thread, and wonder if we can figure out what I have going wrong.

I'm not doing much better than renato120 in the other thread- getting 100 gallons or so out of a dual-canister DI.

Here's the kicker- my TDS out of the RO membrane is 1!
My town water statement isn't very useful- it says chlorine is in the water but it seems kind of vague.
Someone in the other thread suggested a Universal Carbon Block filter, so I ordered one from BRS.

Do you guys have any other ideas what it could be?

 

[Ron Reefman]

Are you saying that you only get 100 gallons of water out of your system before the TDS goes up? You're starting with water at a TDS of 1 after the RO membrane and you only get 100 gallons through the DI before it goes up? Up to what? If you have a TDS of 1 out of the RO, how high is the TDS after the DI? It shouldn't be more than 1.

I have a big RO system and my RO output is zero when new and up to about 2 after a couple of years. But I have big RO membranes. And I make about 500 gallons of RO/DI water a year... maybe more. I get zero TDS after my DI for at least 500 gallons. And I don't worry about the TDS getting up to 2 unless I'm having algae issues in my DT.

This is my Cirqua RO system. The 24" long RO membranes are in the stainless steel tubes.

The DI is just a regular little DI canister and I refill it with bulk DI resin whenever the TDS gets up to 2 to 4. It's in the tan tray under the 40g tank. The 40g tank is RO/DI water and there is also an old cistern that holds 180g of reject water that I use to do laundry. The RO system hanging on the wall above is my old system and I keep it as a back up. It hasn't been used in 4 or 5 years now!

 

[ihavecrabs]

Since so many people here like to trouble-shoot RO systems...

I was amazed to see much people said are getting out of their DI resin in the other thread, and wonder if we can figure out what I have going wrong.

I'm not doing much better than renato120 in the other thread- getting 100 gallons or so out of a dual-canister DI.

Here's the kicker- my TDS out of the RO membrane is 1!
My town water statement isn't very useful- it says chlorine is in the water but it seems kind of vague.
Someone in the other thread suggested a Universal Carbon Block filter, so I ordered one from BRS.

Do you guys have any other ideas what it could be?

Do you know what your tap water tds reading is? Do you have a second tds meter you can verify readings with?

 

[DanConnor]

Sorry, I should have been more clear. The TDS out of the RO is always 1. The problem is that the DI resin depletes very fast anyway. Incoming TDS of tapwater is around 250

 

[DanConnor]

Cool looking system Ron!

 

[jurgenph]

Sorry, I should have been more clear. The TDS out of the RO is always 1. The problem is that the DI resin depletes very fast anyway. Incoming TDS of tapwater is around 250

can you snap a picture of the system, so we can see if it's plumbed correctly?


J.

 

[clm65]

Sorry, I should have been more clear. The TDS out of the RO is always 1. The problem is that the DI resin depletes very fast anyway. Incoming TDS of tapwater is around 250

When you say it “depletes”, are you saying the color changes? Do you monitor the TDS out of the DI unit, and if so, what does it start at and what does it read when the color changes?

 

[DanConnor]

Yes, color changes. The TDS going into the DI is only 1, so I haven't bothered checking what comes out of the DI. Its unlikely that it would be anything other than 1 or 0...

 

[hllb]

I get only maybe 60 gallons before my DI is depleted. But I’m using an RO buddy so the resin container is small. So OP, you’re definitely not alone. I generally only run 4-5 gallons a week. First batch of di resin lasted about 3.5 months. This batch is 3/4 color changed after only 4 or 5 weeks but last time the water was still 0 for a bit after the resin appeared color changed. I refilled it with BRS resin this time and may not have packed it well enough.

so, I’ll follow this thread to see if there are more suggestions.

 

[DanConnor]

It's weird how people get such wide range of results. I'm thinking of just going without the DI, as I'm making about 100 gallons a week and its killing me.

 

[clm65]

Yes, color changes. The TDS going into the DI is only 1, so I haven't bothered checking what comes out of the DI. Its unlikely that it would be anything other than 1 or 0...

True, but it would help rule out incorrect plumbing. For example, if your DI output was on the order of your source water, and the RO output was 1, then there would be an excellent chance that your RO waste water was routed to your DI. Just an easy check to do and provides useful info.

 

[justingraham]

High ph water dissolves does resin faster

 

[justingraham]

What’s your ph after the membrane

 

[clm65]

It's weird how people get such wide range of results. I'm thinking of just going without the DI, as I'm making about 100 gallons a week and its killing me.

indeed. I changed my resin a couple of weeks ago after about a year of service. It was just starting to change color, and my TDS was still 0. I probably ran several hundred gallons or more through it, but my supply TDS is only about 87, so it hasn’t had to work too hard compared to many others.

 

[Silent]

I see only 3 real options for the depleted resin with an input of 1 tds.
1. You have chloramines.
2. You have high ph.
3. Plumbed incorrectly.
Maybe there is more options but these would be top 3.

 

[Silent]

After about 350 or so gallons.

 

[DanConnor]

True, but it would help rule out incorrect plumbing. For example, if your DI output was on the order of your source water, and the RO output was 1, then there would be an excellent chance that your RO waste water was routed to your DI. Just an easy check to do and provides useful info.

My TDS sensor is between the RO and DI canisters, so I don't see how that could happen

 

[DanConnor]

I see only 3 real options for the depleted resin with an input of 1 tds.
1. You have chloramines.
2. You have high ph.
3. Plumbed incorrectly.
Maybe there is more options but these would be top 3.

My town water report says the ph tests all fall between 6.97 and 7.1, so of what you listed I'm thinking chloramine

 

[justingraham]

I would test ur own ph l

 

[clm65]

My TDS sensor is between the RO and DI canisters, so I don't see how that could happen

I guess my point is that you wouldn’t be the first person to have the waste and product lines from the RO reversed. This is a simple test to verify the correct configuration.