One last (hopefully) RODI question

[drknudsenx2]

I greatly appreciate everyone's help over the past week with my used RO system. After much trouble shooting, I could not figure out the problem and decided just to buy a new one that works properly- I picked up a 4 stage Aquatic Life RODI system, which I have just a few questions about.

1) I have a almost brand new 90 gallon/day membrane from the first system, it should work just fine in this system (that came with a 100 g/d membrane)?
2) I had bought a separate DI canister with TDS reader on it, would it be fine to leave the system's DI canister empty and just plumb the separate canister after so that I can use the TDS reader? Or is it necessary to have a DI filter in the system's and in the additional canister? Or should I just bypass the canister on the system?
3) The instructions recommend flushing the membrane for about 30 gallons of produced water, whereas I have read/heard it is fine to flush the membrane for 1 hour or about 5 gallons. Do I need to do the full 30 gallons as recommended?
4) Lastly, it looks like there might be a factory defect with the pressure gauge, is this abnormal/will it affect readings? I checked the pressure coming out of the wall and it was 70 psi, so this is reading 55 psi but I imagine that is just due to slow down from the 2 canisters upstream? Or should I contact the company about it.

Again, I really appreciate everyone's help with all of this, and hopefully I will be able to add to my build thread soon and have this tank up and cycling!

 

[Quietman]

1) I have a almost brand new 90 gallon/day membrane from the first system, it should work just fine in this system (that came with a 100 g/d membrane)? That'll be fine, but of course, slightly less water production.
2) I had bought a separate DI canister with TDS reader on it, would it be fine to leave the system's DI canister empty and just plumb the separate canister after so that I can use the TDS reader? Or is it necessary to have a DI filter in the system's and in the additional canister? Or should I just bypass the canister on the system? You need to run DI media somewhere. If you just want the TDS meter and run a canister empty - no problem as long as you have other canister filled with appropriate DI media
3) The instructions recommend flushing the membrane for about 30 gallons of produced water, whereas I have read/heard it is fine to flush the membrane for 1 hour or about 5 gallons. Do I need to do the full 30 gallons as recommended? Follow manufacturers directions is always best (that said, I did not and only flushed a few gallons). To extend life of membrane, having a bypass valve to flush membrane before/after and every few hours of water production is beneficial. I flush a gallon before and after (I only make 20 gallons at a time, so no need to flush in the middle).
4) Lastly, it looks like there might be a factory defect with the pressure gauge, is this abnormal/will it affect readings? I checked the pressure coming out of the wall and it was 70 psi, so this is reading 55 psi but I imagine that is just due to slow down from the 2 canisters upstream? Or should I contact the company about it. If you're talking about the air bubble..that's fine not a defect. It's needed for correct dampening of the fluctuations (or some such design thing).

 

[PatW]

1) Your new RO membrane should work fine.

2). I flush until I get a reading of 6 tds. I then put it on normal flow and wait until it reads 2 tds before running it through the DI canisters. The flushing both sides takes about 20 minutes.

 

[drknudsenx2]

Thanks y’all! We are up and running and the TDS before is 1 and after DI is 0. Next up is to make the salt water.

 

[Albertan22]

You shouldn’t be losing pressure through your canisters unless they are leaking. Is the pressure gauge plumbed in before the RO membrane? If it’s after for some reason then you’d see the pressure loss from the waste line sending it down the drain.

 

[drknudsenx2]

You shouldn’t be losing pressure through your canisters unless they are leaking. Is the pressure gauge plumbed in before the RO membrane? If it’s after for some reason then you’d see the pressure loss from the waste line sending it down the drain.

I believe the pressure gauge is after the membrane, so that would make sense. I think that is the pressure going into the DI

 

[Albertan22]

I believe the pressure gauge is after the membrane, so that would make sense. I think that is the pressure going into the DI

Ok then that’s your reason, most units measure the pressure going into the membrane, weird that yours is different but at least you have your explanation.

 

[drknudsenx2]

Ok then that’s your reason, most units measure the pressure going into the membrane, weird that yours is different but at least you have your explanation.

No, you’re right- it says the pressure gauge is to measure incoming water. I’m not sure why there is a 10-15 psi difference, there are not any leaks and appears to be running appropriately.