I have a 75 gpd 6 stage RO/DI unit that I just recently change the RO cartridge and all the other cartridge as well. Prior to the change I was getting 0 ppm coming out of the RO and into the DI. Since the change I’m now getting 4-5 ppm coming out of the RO.
Is this normal since the cartridge is new? will my water coming out of the RO be 0 ppm again like it was? Did I do something wrong and that’s why the water is not 0 ppm coming out of the RO filter portion. I did recheck the cartridge and make sure it was put in right and seated right and it was.
Anybody have any clue as to why it’s doing this? Thanks
i get about 2-3 from ro i recently upgraded to a 75gpd and it was real high in the beginning then 25ppm after 5-10 gallons now its back to 2-3 i think the carbon particles caused mine to get high
How much water has went through the new ones about s far?
Let the water run through it A it should come back.
Also depends on the tds going into the unit if it's real high you may get a little coming out the other end but it could also be sediment in the containers from changing them.
If I remember mine did the same thing the last time I changed them.
[quote=“The Reef Hut, post:2, topic:5832”]
I have never had 0 out of the ro into the Di I get 3-5 I think it is impossible to get 0 tds without a Di[/quote]
It would first come out about 20 to 30 during the flush then slowly down to 0 once I turn off the by pass valve. According to my TDS meter anyways.
[quote=“Hudzon, post:3, topic:5832”]
could be the RO filter itself you may of had a good 98-99% before and now a fair 96-98% now[/quote]
And it could possibly be.
[quote=“dunk, post:4, topic:5832”]
i get about 2-3 from ro i recently upgraded to a 75gpd and it was real high in the beginning then 25ppm after 5-10 gallons now its back to 2-3 i think the carbon particles caused mine to get high[/quote]
Also, that my be the case as well, since I did replace the other cartridges as well.
[quote=“billrob71, post:5, topic:5832”]
How much water has went through the new ones about s far?
Let the water run through it A it should come back.
Also depends on the tds going into the unit if it's real high you may get a little coming out the other end but it could also be sediment in the containers from changing them.
If I remember mine did the same thing the last time I changed them.[/quote]
I say so far it has been about 75 g has been produce. I guess I could test the water going into the the unit to see how high the TDS is.
I agree with the guys, mine seemed to settle down lower after a second batch of water…
did you happen to get a membrane with a diff rejection rate then your old one? any changes in water pressure?
I’m not a math wiz A, but i think you can figure out if everything is correct by tds in, tds ro out, and the rejection rate of the membrane… I snagged this off the net, hope it helps… it should tell you if the membrane is working up to par…
[b] RO Membrane Performance Test
The performance of a RO membrane is measured in terms of its rejection charac- teristics.
Important: Test the quality of the membrane once every 6 months.
Procedure:
Measure tap water tds. (Call it X)
Run the system for 15-20 minutes.
Rinse test instrument cell 2-3 times with RO water.
Measure RO water tds. (Call it Y).
Subtract RO water tds from tap water tds. (X - Y)
Divide this quantity by tap water tds. (X - Y) ÷ X
Thanks John for the test procedure, I’ll give it a try.
My unit came from the filterguys and I decide to buy/change the cartridge from BRS since they had a sale during the holiday. It’s 75 gpd RO TFC cartridge and I figure since it the same DOW brand TFC it should be the same.
I use a booster pump for the unit and it’s pushing the same pressure as the last set of cartridge, according to the pressure gauge.
[quote=“saltcreep, post:7, topic:5832”]
did you happen to get a membrane with a diff rejection rate then your old one? any changes in water pressure?[/quote]