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SteveM10
02/01/2013, 05:56 AM
I have a Typhoon III RO/DI system. I recently moved and have set it us with all new filters and membrane. I used to always get a reading of 0 TDS in my last home but in my new home the best I can seem to get is 7 TDS. Tap water reads 168 TDS. My water pressure is at 50 psi.

Any suggestions for getting it to 0?

bugs713
02/01/2013, 06:00 AM
Maybe get your pressure up to 60+??

What was tap water TDS at the previous home?

SteveM10
02/01/2013, 06:06 AM
Maybe get your pressure up to 60+??

What was tap water TDS at the previous home?

I'm not sure, I never checked it because I always had 0 TDS.

I was thinking about trying to boost the pressure, just wasn't sure if that would help or not.

Buckeye Hydro
02/03/2013, 01:04 PM
I have a Typhoon III RO/DI system. I recently moved and have set it us with all new filters and membrane. I used to always get a reading of 0 TDS in my last home but in my new home the best I can seem to get is 7 TDS. Tap water reads 168 TDS. My water pressure is at 50 psi.

Any suggestions for getting it to 0?

More pressure is always good, but at 50 psi that's probably not the problem.

Do you have a Filmtec membrane?

We need one more TDS reading to start the troubleshooting. What is the TDS of your RO water?

How are you measuring the TDS?


Russ

SteveM10
02/03/2013, 09:15 PM
More pressure is always good, but at 50 psi that's probably not the problem.

Do you have a Filmtec membrane?

We need one more TDS reading to start the troubleshooting. What is the TDS of your RO water?

How are you measuring the TDS?


Russ

Not sure what membrane it was. It was never used and I got it from the Air Water Ice web site when I ordered the replacement filters a couple of years ago.

The RO only reading is 20.

I am using the TDS-3 meter that I received with the unit. I do have a second TDS unit and that one reads 26 on the RO water.

Buckeye Hydro
02/04/2013, 04:16 AM
OK. With your tap water at 168, and your RO water at 20, and assuming these readings are accurate, you're getting only an 88% rejection rate. That's pretty poor membrane performance. You'll go through a full size (10" x 2.5") vertical DI cartridge in about 250 gallons.

If you had a better membrane and had a 98% rejection, your RO water would read about 4 ppm, and you'd get about 1250 gallons from a DI cartridge. That is, a better membrane would pay for itself in short order.

But that doesn't really address your original question - How do you get 0 pppm water from your DI cart? If you're getting something other than 0 ppm from a new cartridge, here's some suggestions:
*Make sure to use quality DI resin
*Make sure your DI resin isn't old, been exposed to air, or dried out
*Make sure your DI cart is packed very tightly
*Make sure your DI cart is vertical
*Make sure you take your water sample for TDS testing AFTER the TDS creep period, and make sure you use an absolutely clean glass sample container.

Russ

keithhays
02/04/2013, 05:53 AM
I would get the pressure pump which will put you into the 80 to 90 psi range which will improve the performance of your RO membrane. And, I would put in an additional DI canister if you don't already have two.

Buckeye Hydro
02/04/2013, 06:40 AM
Hmm - boosting the pressure in this psi range will improve rejection, but only a little. Adding resin will lengthen the time between resin changes, but it doesn't address the real issue - which is poor membrane performance.

keithhays
02/04/2013, 06:51 AM
Hmm - boosting the pressure in this psi range will improve rejection, but only a little. Adding resin will lengthen the time between resin changes, but it doesn't address the real issue - which is poor membrane performance.

I will go with on that, but I would still do the others.

wilsonreefs
03/01/2013, 02:23 PM
After you installed your new membrane and filters, (assuming you changed your DI media as well). I always back flush my Membrane for about 20 gallons, and run the ro/di for about 10 gallons to flush everything out. I don't know how long you've been running the RO/DI after the change, but it should level out back to 0. If it doesn't, your membrane may be bad.

Carl

Buckeye Hydro
03/01/2013, 03:12 PM
New membrane performance reaches "normal" levels after 6 to 24 hours of run tiime. DI resin needs to be flushed w/ about 3 bed volumes of water.

Russ

SteveM10
03/01/2013, 06:23 PM
Thank you. I did replace the DI resin and now it is now reading 0 so all is good.

oldsaint
03/09/2013, 09:06 PM
Thank you. I did replace the DI resin and now it is now reading 0 so all is good.

If you didn't address your membrane issue you'll burn though more DI than necessary.

Buckeye Hydro
03/10/2013, 03:14 AM
if you didn't address your membrane issue you'll burn though more di than necessary.

+1.

oct2274
03/11/2013, 09:48 AM
I have a Typhoon III RO/DI system. I recently moved and have set it us with all new filters and membrane. I used to always get a reading of 0 TDS in my last home but in my new home the best I can seem to get is 7 TDS. Tap water reads 168 TDS. My water pressure is at 50 psi.

Any suggestions for getting it to 0?

Did you fast flush for atleast 10-15 minutes after installing the new membrane?

What is the TDS of the water coming out of the RO only line? - if that is extremely high, you could have an issue with the new membrane, or you might try reseating the membrane. When you reseat the membrane, make sure it is pushed in all the way. It sometimes takes a bit of force. I would apply magic lube to the o-rings on the membrane as well as the black collar that makes the seal against the housing. You can get the magic lube from home depot or various other places. You don't need to use alot, just enough to lubricate it.

After reseating the membrane, fast flush for 5-10 minutes, then run the RO only line to a clean 5 gallon bucket and let if fill. Once that is full, dump that water, then fill it again high enough to test the water with your tds meter, what is the reading? It should be below 10. I say to run the RO only line because there is no use in wasting DI resin till you figure out if your membrane is bad.

Let us know how things turn out!