Ro/Di died (i think)

[Dj City]

Hello

I have an Aquamaxx Puratech RO/DI unit. I've had it for quite a few years and it has always performed flawlessly.
It's the one with the micro processor that flushes automatically and has the attached booster pump as well as digital tds reader.

I have it set up to automatically produce water when the "low" sensor in my ato reservoir is dry and shut off when the "hi" sensor is wet. This is done via Hydros and a solenoid.

Today, I noticed it was not making water when it should have.
I thought the hydros solenoid went bad so I tested it. I hit the open tab in hydros and can hear the solenoid engaging. The solenoid is opening and closing as it should.
I checked the source water and i have water pressure from the source to the RODI unit.
I unplugged the RODI and plugged it back in to test the unit. It pressurized and flushed as it should but that's about it. The display is working as it should but water is not going through the unit. The booster pump is not kicking on and water is not flowing through.

My thoughts are that either the booster pump is toast or the solenoid or solenoids are toast.
I would think that even without the booster pump kicking on, water should still flow if the solenoid to the ato is open. It would just flow slowly.
I could be wrong though.
Does the booster pump only engage when presented with water?

I'm looking for advice and guidance on how to diagnose the fault and how to fix it.

I believe there are 3 solenoids in this unit. If one or some of them are not working, can this stop the booster pump from coming on?

If anyone has any experience with this and can point me in the right direction on how to diagnose and fix...
I would be very appreciative.

 

[tbrown]

When did you last change the DI resin and RO membrane? Do you have pressure gauges anywhere else or just on the inlet?

 

[tbrown]

But yes, depending on how the booster pump is set up, over pressuring (downstream solenoid not opening) can cause the pump not to run. If the booster pump has a "run dry" protection feature and an upstream stolen not opening can cause the pump not to turn on.

 

[Dj City]

But yes, depending on how the booster pump is set up, over pressuring (downstream solenoid not opening) can cause the pump not to run. If the booster pump has a "run dry" protection feature and an upstream stolen not opening can cause the pump not to turn on.

Thank you.
I've attached pics of my RODI.

Which solenoid should I be looking at?

 

[Dj City]

I said earlier that the unit has 3 solenoids but that was incorrect. It only has 2 solenoids a high pressure switch.

Which one should I be looking at?

 

[tbrown]

The "Reservoir Full" light is lit. I assume that is based on downstream pressure.

How difficult is it to remove the line from the Hydros solenoid just to verify you don't have water at that point?

If it's not the Hydros solenoid, it's likely going to be the downstream solenoid on the RODI.

 

[Dj City]

The "Reservoir Full" light is lit. I assume that is based on downstream pressure.

How difficult is it to remove the line from the Hydros solenoid just to verify you don't have water at that point?

If it's not the Hydros solenoid, it's likely going to be the downstream solenoid on the RODI.

I've already done that and the Hydros solenoid. That's good.

Which one is the downstream solenoid?

 

[tbrown]

It's hard to tell but I think they both might actually be downstream. One is after the RO membrane, the other is after the DI chamber?

If so, the left one is likely after the DI membrane and that's going to be the furthest downstream solenoid.

 

[Dj City]

I found the problem!

The solenoids are all working as expected but the high pressure switch went out.

I jumped (bypassed) the switch and have water flowing! No booster pump but at least I have RO/DI water.

I went ahead and ordered a new high pressure switch that will fix my problems!

 

[tbrown]

I found the problem!

The solenoids are all working as expected but the high pressure switch went out.

I jumped (bypassed) the switch and have water flowing! No booster pump but at least I have RO/DI water.

I went ahead and ordered a new high pressure switch that will fix my problems!

Makes sense. It triggered high pressure and activated the "Full Reservoir" alarm and likely closed the solenoids.