What would cause RO/DI output to almost go to zero?

[porpoiseaquatics]

I just changed all the filters in September...including the DI resin. Until today, it's been doing fine. A little slower than normal but I attributed that to the colder water temps. Now today, it's produced almost nothing after running for 8 hours. It should've produced about 20-30g in that amount of time. Any suggestions in what to look for?

 

[rjrgroup]

How many days between running? You can build up a bacterial slime coat on the RO membrane in less than a week without running. It will essentially clog the micro pores on the membrane film. Just a thought...

 

[acroholic]

Are you still producing waste water?

 

[porpoiseaquatics]

rjrgroup;939633 wrote: How many days between running? You can build up a bacterial slime coat on the RO membrane in less than a week without running. It will essentially clog the micro pores on the membrane film. Just a thought...

Usually a week. It's how I've produced water for over 3 years now without a previous issue.

 

[porpoiseaquatics]

Acroholic;939641 wrote: Are you still producing waste water?

Yes and it appears to be a normal flow.

 

[sn4k33y3z]

Jeff, has the pressure in your domestic water system changed?

 

[porpoiseaquatics]

Sn4k33y3z;939656 wrote: Jeff, has the pressure in your domestic water system changed?

No change in the incoming pressure.

 

[sn4k33y3z]

Silly question and I'm sure you've looked it over, but any chance there's a kink in the line somewhere or is there a valve shut? My next thought is, perhaps the system has an air bubble somewhere in it and it's air-locked maybe...

 

[tngyen813]

Try taking the filters out and see if the carbon has broken apart and is clogging up the system


Sent from my iPhone using Tapatalk

 

[acroholic]

porpoiseaquatics;939643 wrote: Yes and it appears to be a normal flow.

Look at your input pressure. If normal then look for your problem in the RO membrane forward. It would not be in the sediment filter or the pre or post carbon filters because it would be affecting the waste water as well. Look at the membrane, or the line from the membrane to the DI, the DI, or the line from the DI to your reservoir as the source of the issue.

Disconnect the line from the DI and if you can blow through it, then that is not the source of the issue, and it is somewhere between the RO membrane and the DI container.

 

[porpoiseaquatics]

Thanks guys for the input....I'll take it apart and try a few of these tomorrow.

 

[ralph atl]

I had that issue a few times...

albeit I changed a bunch of stuff out first, no biggie.

1. one line was not all the way "set in" connector to "auto shut off valve"
2. "flow restrictor" broken

 

[porpoiseaquatics]

How would I test the RO Membrane? It's not been changed in about 2 ... maybe even 3 years. I just go by my output TDS and that's 0 currently.

 

[acroholic]

porpoiseaquatics;939681 wrote: How would I test the RO Membrane? It's not been changed in about 2 ... maybe even 3 years. I just go by my output TDS and that's 0 currently.

Pull the RO product water line off the DI container and turn the RO unit on. If the membrane is working you'll have product water. Then you can rule that part out and you'll know the problem is the DI container or the line from the DI to the reservoir.

 

[picoreefguy]

also check your flush valve maybe you were flushing the system and forgot to close the valve afterwards?

 

[rjrgroup]

Acroholic;939683 wrote: Pull the RO product water line off the DI container and turn the RO unit on. If the membrane is working you'll have product water. Then you can rule that part out and you'll know the problem is the DI container or the line from the DI to the reservoir.

+1

Also, it's highly unlikely after that amount of time operating fine but I have seen Teflon tape work it's way loose somehow</em> and block the line.

 

[acroholic]

But do make sure to check the line pressure first, because a drop in line pressure would fit in to exactly what you are describing. RO production would cease first in a membrane and waste water would continue if your line pressure dropped too low.

The line pressure is what forces water across/through the membrane and pushes the product water out the product water line, and if your line pressure is below or just at the threshold pressure required by the membrane you have, no or little product water gets made.

 

[porpoiseaquatics]

I took a couple of lines off the unit today and found water flow at each point. I think I'm down to one of two possible issues....1) the RO Membrane maybe slightly clogged and needs to be changed...after all it has been about 3 years or 2) the auto-shutoff is bad (Air, Water & Ice unit). I don't have it connected to need the auto shutoff but the lines still run through it. I believe it's operation is based off of back pressure. I may bypass it and see if output increases.

Today it appears to be making a good deal more water than it did yesterday.