Whats wrong with my RO?

vcnt

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I just fired up my ro di unit and I was reading 87 tds going into membrane and 0 out of DI resin, but I had 40 psi. I just ordered a new sediment filter (1 micron) and i think that is why the low psi. The unit was used by someone who gave me all of their stuff because he didn't want it anymore
 

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I just fired up my ro di unit and I was reading 87 tds going into membrane and 0 out of DI resin, but I had 40 psi. I just ordered a new sediment filter (1 micron) and i think that is why the low psi. The unit was used by someone who gave me all of their stuff because he didn't want it anymore

Without more info nobody knows. What is your pressure before the unit?

I don't even worry about pressure. 99% of municipal water comes in with plenty of PSI. After your membrane you should be 99% reduced TDS. So if you are 100 TDS before the membrane you should be at 1TDS after. Then the DI should bring it to 0. Check your TDS before your membrane and then after. That way you can confirm the membrane is still good.
 
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vcnt

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What’s the water pressure on the city line? Also, what is the ratio of wastewater to RODI?
I don't know the pressure from the city, the intake is just screwed onto my garden hose. There was definitely a lot more waste than pure, but I assumed it was due to low pressure
 

The_Paradox

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I don't know the pressure from the city, the intake is just screwed onto my garden hose. There was definitely a lot more waste than pure, but I assumed it was due to low pressure

Usually there is a valve to control back pressure somewhere on the waste line. You should be getting something like 3:1 waste to finished. Without knowing the municipal lines water pressure there is really no way of knowing if anything is causing undo back pressure.
 

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Is there a valve to shut the output off? If so what is the pressure with it off?
 
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Usually there is a valve to control back pressure somewhere on the waste line. You should be getting something like 3:1 waste to finished. Without knowing the municipal lines water pressure there is really no way of knowing if anything is causing undo back pressure.
image.jpg

There’s my waste water line
 

The_Paradox

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What’s ratio of finished to waste water? In a pinch, pun intended, you could just kink the end of the waste water until the ratio of waste water was correct then check the pressure. If that’s all it takes you just need a cheap quarter turn valve.
 

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I just fired up my ro di unit and I was reading 87 tds going into membrane and 0 out of DI resin, but I had 40 psi. I just ordered a new sediment filter (1 micron) and i think that is why the low psi. The unit was used by someone who gave me all of their stuff because he didn't want it anymore
In my mind, 87 out of the source is quite good but it’s important to test what comes out after membrane. If it’s not reducing your 87 to say 3-5ppm, your DI will exhaust very very quickly.

My city water is 40 ish Psi but I’ve never placed any thought to that.
 
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vcnt

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In my mind, 87 out of the source is quite good but it’s important to test what comes out after membrane. If it’s not reducing your 87 to say 3-5ppm, your DI will exhaust very very quickly.
I have installed the HM Digital TDS Meter, it only has 2 probes
 
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In my mind, 87 out of the source is quite good but it’s important to test what comes out after membrane. If it’s not reducing your 87 to say 3-5ppm, your DI will exhaust very very quickly.

My city water is 40 ish Psi but I’ve never placed any thought to that.

I have installed the HM Digital TDS Meter, it only has 2 probes
Im going to remove the DI and attach clean water line right out of membrane
 

Uncle99

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Im going to remove the DI and attach clean water line right out of membrane
As long as it less than 5 ish, your membrane is functioning correctly.

I’m not sure why PSI is a factor in your case if you can reduce 87 to 5 and DI to zero.
 
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As long as it less than 5 ish, your membrane is functioning correctly.

I’m not sure why PSI is a factor in your case if you can reduce 87 to 5 and DI to zero.
its making water very slow, I have 2 90 gpd. You're saying out of membrane should be 82 or 5?
 
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KStatefan

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Can not determine what you need to do with out source water pressure.

The membrane should reduce the TDS at least 90% but most of the membranes will be 95% or greater.
 

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