Unresolved RODI float valve shutoff

Ok, not a DIRE emergency but I bought and RODI unit today abd got a float valve to go into my container to shut it off once it reaches full. Can i leave it going all night? When the shut off valve closes when it reaches the float will the unit just stop or will it push it all out the waste side? Will it cause an excess pressure build up in the system?

 

I was hoping to try and get some sleep....

 

The unit will shut itself off IF it is equiped with an automatic shut off valve. The most common type of ASOV looks like the one on the right below. These ASOV's are typically plumbed in behind the horizontal RO membrane housing. On poorly plumbed (ebay) units you'll sometimes find them in front of the RO membrane housing.



If your unit doesn't have an ASOV, then the float will stop the flow of purified water, but the waste water will run and run and run... 24/7, unless or until you manually shut off flow to the system.

No worries re excess pressure building up inside the system.

Russ

 

I just installed an ASOV exactly as the instructions said and I even confirmed with the YouTube install video, but FAIL, the drain line continues to run gangbusters after my float stops the RO flow. It didn't come with a flow restrictor for the drain line so I thought maybe that was the problem so I put a ball on that to restrict flow just to test it but still, no good. Thoughts?

 

All RO/DI units should come with a flow restrictor!
What did you buy? Some restrictors such as Buckeye and Spectrapure supply are not visible but still present inside the waste line.

Post some photos of your plumbing, its ev=xtremely easy to hook up a ASOV incorrectly, I do it myself sometimes.

Did you install a check valve along with the ASOV? Most ASOV's will work better with one in the circuit such as pictured here:
http://www.spectrapure.com/huds/ASO-SYS.pdf

 

I've had two float valves fail to seal resulting in a flood. I'll never use them again.
They may work great for a while, but it only takes one time to wake up to a wet floor and severe hyposalinity in the aquarium. Not worth it to me.