Gravity Fed ATO w/ Solenoid - not working properly

[AquAttila]

Hi,

I am curious if anyone has configured a gravity fed ATO w/ float valve successfully working - controlling with Apex (i.e. salinity probe).

I attached a few pics of my setup, and assume my problem is that the pressure from my RO holding tank is not strong enough so solenoid will not allow water to pass. I want to control the valve with apex if the salinity drops to a specific gravity to turn valve ON and shutoff water from passing to the sump.

 

[T-J]

If the blue line in the third pic is your top-off line, I see the valve is closed. Not sure if you had it open when testing.

More importantly, I have a question: If the solenoid were to fail in the open position, wouldn't that cause all of your RO water to empty into the sump?

 

[AJsReef]

If the blue line in the third pic is your top-off line, I see the valve is closed. Not sure if you had it open when testing.

More importantly, I have a question: If the solenoid were to fail in the open position, wouldn't that cause all of your RO water to empty into the sump?

+1 here, valve appears closed, I'd also highly encourage a float valve in the sump if you don't already have one

 

[Subsea]

Without physically seeing your system, It looks to me as if 1/4” tubing feeding solenoid is in a syphon configuration. If so, that can be your problem. I suggest a bulkhead connector at bottom of barrel.

@attilak
Can you better describe volume of ato compared to system volume. If solenoid fails open, is ato volume enough to overflow sump?

Where is float valve located in your system? A flow schematic would help.

 

[AquAttila]

If the blue line in the third pic is your top-off line, I see the valve is closed. Not sure if you had it open when testing.

More importantly, I have a question: If the solenoid were to fail in the open position, wouldn't that cause all of your RO water to empty into the sump?

correct, it is turned off because I had an issue with my top off, hence the reason for my post.

If you look at the second pic, there is a float valve so if the solenoid where to fail in the open position it would only fill sump until the float valve allows.

 

[AJsReef]

Trying to understand better, you aren't getting any flow right? I assuming these solenoids are the same as the Apex branded in which power "on" allows flow and "off" prevents flow. In other words, solenoid "on" = flow.