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How Long Do You Flush Your RO Membrane? (1 Viewer)

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Cody

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After upgrading to an 8-stage RO system with TDS meters after each stage, I’m getting a lot of insight into what happens with each stage. The biggest take away so far is how long to flush my membranes so that the DI resin isn’t getting blasted with gunk. Looks like it takes about 3-3.5 minutes for the output from the RO membranes to drop from the 50s to 5-7ppm. I have always flushed for 5 minutes based off of a general recommendation but it’s nice seeing the actual numbers.
 

BigRick

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Same I just wait for the drop.. sometimes 3 minutes sometimes 5... meter between every stage after carbon blocks. Cations gets hit hard and from there zero anion and Zero mixed DI resin.
 

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i usually do about 30 minutes on the carbons and then another 30 minutes on the membrane.. probably too much but figured it couldn't hurt much except my water bill.
 

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i usually do about 30 minutes on the carbons and then another 30 minutes on the membrane.. probably too much but figured it couldn't hurt much except my water bill.

Oh man that’s a big waste.

You need this very affordable and automatic flush - booster pump. I’m using the below:


 

Team Turtle

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Oh man that’s a big waste.

You need this very affordable and automatic flush - booster pump. I’m using the below:


I've been looking at this..what kind of pressure are you getting out of it. My normal water is around 45 psi so using the 8800 to get it to 80
 

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After upgrading to an 8-stage RO system with TDS meters after each stage, I’m getting a lot of insight into what happens with each stage. The biggest take away so far is how long to flush my membranes so that the DI resin isn’t getting blasted with gunk. Looks like it takes about 3-3.5 minutes for the output from the RO membranes to drop from the 50s to 5-7ppm. I have always flushed for 5 minutes based off of a general recommendation but it’s nice seeing the actual numbers.
5-10 minutes for me. Watch meter until tds drops below 10 then will close bypass. If it goes back up above 100 i open for a few more minutes and try again.
 
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Cody

Cody

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5-10 minutes for me. Watch meter until tds drops below 10 then will close bypass. If it goes back up above 100 i open for a few more minutes and try again.
So you actually have to flush yours in mid operation? Once my water hits 2ppm coming out of the RO membrane, it never raises and I make about 225 gallons per sitting.
 

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So you actually have to flush yours in mid operation? Once my water hits 2ppm coming out of the RO membrane, it never raises and I make about 225 gallons per sitting.
No, just before i start making new water. Best i get coming out of two membranes is 7 tds...wish i could get down to 2. I burn di like i get it for free. But just switched to the single stages of resign and then a mixed bed so will see how that helps consumption.
 
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Cody

Cody

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So I ended up firing up the RO unit again tonight and watched the gauges. Turns out, the water coming off the membrane peaks up to the mid 90s real fast and then hits 7ppm in about three minutes again. I didn't recall it hitting the 90s last time, but the three minute turn around on on getting it down to 7ppm, then pushing it to 2ppm with the flush valve closed and the booster on is nice.
 
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Cody

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Daannng...whats your pressure before pump?
You’re not getting that high? Mine is 90+ too with a booster. It’s about 50 with no boosters, I believe.
 

Erin

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With the 8800 crank all the way up I'm getting to 90 after the first membrane going into 2nd.
So the booster is after the first membrane? What are you getting going into the first membrane?
 

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Ro booster should be before all membranes.

Im doing 100 psi on my ro membrane. Gonna go nuts and install a controller on my ro system. Tds monitor to shut off ro unit is it reads 1 tds Email/text me. Also water leak detectors scattered around for safety.
 
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