What's up with my RODI tds?

[Smite]

Hey all,

I'm lost on my RODI setup and could use some help. I noticed I was going through DI resin quickly and saw I had silicates in my ATO and DI water container from an ICP test. I realized my tds had creeped up to 20 +- tds going into my DI stages so I replaced my carbon blocks and membrane. After swapping I'm getting 24 TDS after the membrane going into DI, so essentially the same reading....

Here is my Setup layout:

Prefilter 1 micron
Chloramine Monster (BRS) I did not replace this its about 2 years old but I dont have the funds right now
.5 Micron Carbon Block (MD)
.5 Micron Chloramine Block
RO Buddy Booster pump (A little high at 100 psi) going to membrane
2 Stage DI - Bulk Reef DI followed by SpectraPure Silicabuster Cartridge

Going into my Pre filter I have 345 TDS. It reads 375 TDS after the carbon/chloramine stages headed to 75GPD RO Membrane (Marine Depot forgot manufacturer). This has always done this and I can't figure it out. I figure I should be seeing 4-8TDS with the 98-99% membrane rating headed to my DI stages but instead I'm getting 24 tds. When my RODI was last working well once it settled the TDS would be about 8 heading to my DI Stage

When I swapped filters I bypassed the membrane and flushed the blocks for 30 minutes. I then hooked the RODI membrane up and made 50g before adding my DI stages. I made another 50gs, so I'm 100 in on the membrane and it only dropped down to 24 GPD.

What could I be over looking here? Will 100 PSI smoke a membrane? I'm going to move my sensors around to eliminate a bad sensor as that just occurred to me. I tore open the top of the plastic RO membrane bag and installed it without touching it, pushed in hard to make sure it seated.

I see no leaks. I've turned the membrane in all different directions to release any trapped air incase that was throwing it off. I'm at a loss!

I'll report back after verifying the TDS but any insight is greatly appreciated.

Thanks

Matt

 

[shwareefer]

Maybe some bypass in the housing? You could try making a few gallons without the booster pump to verify.

 

[Smite]

Maybe some bypass in the housing? You could try making a few gallons without the booster pump to verify.

By that you mean a bad seal, so not all water is making it through the filter?

Are you saying if I remove the booster bypass would be less and tds would drop?

 

[shwareefer]

By that you mean a bad seal, so not all water is making it through the filter?

Are you saying if I remove the booster bypass would be less and tds would drop?

Every rubber seal has a limit, it doesn't have to be bad. Unpluggin a booster pump from the wall is a simple test.

 

[WayneF1]

Do you have a way to check the pressure drop across you RO membrane? Should be about 4-5 PSI, higher or lower than that indicates a different problem. and yes 100 PSI going in a too high, general theory is 60 - 80 PSI

 

[KStatefan]

The Filmtec membranes are rated for 150 psi

 

[Chrysemys]

I had a similar issue at one point, something had happen with my flow controller. If I remember correctly, it was at a lower flow than it should have been. I replaced that and all was good.
Sometimes on the lower gpm units the flow controller in not a separate part. I’ve seen it incorporated into one of the fittings.

 

[zalick]

Edit: reread your post and see it's happening with a new membrane.

Let us know results of swapping TDS meters. That seems a possibility.

 

[shwareefer]

I had a similar issue at one point, something had happen with my flow controller. If I remember correctly, it was at a lower flow than it should have been. I replaced that and all was good.
Sometimes on the lower gpm units the flow controller in not a separate part. I’ve seen it incorporated into one of the fittings.

A clogged flow restrictor. That makes sense. The OP didn't mention if it was replaced with the membrane.

 

[Reef.]

I’m a little lost with what you have done, so sorry if I miss something.

Did you also flush the membrane for an hour before use, by passing the resin?

100psi will be more than fine, best place for the booster is after the filters and before the membrane, will still work if you have it at the start but best before the membrane.

You should be taking readings after the membrane which should give you the 97% reading or whatever your membrane specs state, and a reading at the end where it should be zero, are you getting these figures?

 

[Smite]

I did not change the flow restrictor when I replaced the membrane and to be honest I’m trying to remember if the booster pump had me eliminate that altogether I didn’t think about that going bad, I just stuck with the 75 GPD rated membrane so that is something I’ll be looking into.
Unfortunately I can’t just turn off the booster to test quickly. it restricts flow and controls the ro unit. I’ll have to by pass it completely to test.

the booster is hooked up after the pre filters. It hits the pressure gauge and the directly to the membrane. My reading going into the membrane is 375, leaving the membrane is 24. The membrane is rated at 99%.

I’ll be referencing this thread and troubleshooting my unit later this afternoon. I’ll report back with any findings. Thanks for all the help so far.

 

[Smite]

So I went through the RO Buddie booster pump install instructions and it does request that the flow restrictor be removed. Once I check my tds sensor orientation, if that doesn't solve my issue I'll be moving on to bypassing my booster completely.

 

[zalick]

I just watched an install video for the booster buddy. You might want to watch a video to make sure you have all the tubes connected correctly. That pump manages your flow restriction so you don't need the additional restrictor that came with the RO unit.

Do you know what your current waste:to ratio is?

 

[Smite]

I just watched an install video for the booster buddy. You might want to watch a video to make sure you have all the tubes connected correctly. That pump manages your flow restriction so you don't need the additional restrictor that came with the RO unit.

Do you know what your current waste:to ratio is?

I don't I have my wast line set into my washer drain. I'll look into that as well, thanks!

 

[Buckeye Hydro]

Feel free to give us a call when you are in front of the system if you still need help.

Russ