RO problem

[jaustin]

I just replaced the membrane, sed filter, and carbon filter and my tds is 40. I let it run for 12 hrs and 40 is as low as it's gone. My tap water is 167 and the water temp is cold....would that have anything to do with the TDS? I think the temp is in the 40-50s. Would a DI unit handle 40 TDS and not ware down the resin too fast?

Thanks, oh and it's a Coralife pure flo with a 22 GPD CTA membrane and my water pressure is 50 psi.

Thanks
Jason

 

[FutureInterest]

I think 40 TDS is way too high for resin. You'll run through it very very quickly.

The temperature of the water does make a lil difference. It will typically run more sluggish with colder water. Its not a big deal though.

The psi might be your problem. Most membranes requires 50psi at a bare minimum. I don't know about that particular membrane though... You'll have to contact the manufacturer and find out for yourself. You may end up having to get a booster pump.

You may want to check and see if all your filters and the membrane are installed correctly. Its possible that some of the water is bypassing a filter/membrane somewhere.

 

[roland jacques]

I agree with Jin-O. I think your Membrane may not be seated properly. Check the seals/o-ring... or the membrane got dryed out, or very old, defective...

Slightly low pressure and cold temps just waste extra water, lower water production, and work a little harder on the membrane, but they should not raise the TDS.

 

[jmaneyapanda]

FutureInterest;145340 wrote: I think 40 TDS is way too high for resin. You'll run through it very very quickly.

The temperature of the water does make a lil difference. It will typically run more sluggish with colder water. Its not a big deal though.

The psi might be your problem. Most membranes requires 50psi at a bare minimum. I don't know about that particular membrane though... You'll have to contact the manufacturer and find out for yourself. You may end up having to get a booster pump.

You may want to check and see if all your filters and the membrane are installed correctly. Its possible that some of the water is bypassing a filter/membrane somewhere.

agreed. Espoecially check that those little foam rubber bushings are in place on the sediment and GAC blocks, and that the RO membrane is firmly seated in the housing.

 

[jaustin]

the sediment filter doesn't have any kind of rubber bushings, it just sits in the canister. Should there be rubber bushings on both ends? The Carbon one has them but not the sediment.

I reseated the ro membrane, the membrane is new and the o ring on the end is new, also it's pushed in all the way.

Thank you all for the help.

 

[roland jacques]

Normal sediment filters don't have gaskets.

CTA membranes have poor rejection rates, and they don't last very long. normal a CTA rejects 85-90%. yours is doing about 70-75 % so it sound like your membrane is defective. (it can be new to you. but old form seating on a shelve for 10 years)

Id get a good TFC membrane it will pay for itself in a years time vs what you have

 

[roland jacques]

With a 96-98% TFC membrane your TDS would be 4-6TDS

 

[jaustin]

i can put a TFC membrane in my current setup? I would have to re rout the carbon block so that the water goes through the sed then the carbon and then the ro membrane.

thanks again