Which RODI valve to close when not in use

Levinson · Sep 10, 2020

I've just installed RODI unit for the first time and it's working great, thanks to some of the advices from r2r.
I've got some questions which may sound stupid but thought it wouldn't hurt to ask. I didn't have much luck finding the answers online.

1. Do you keep the RODI unit pressurised (with the valve from the water source kept open) and mount a valve on the outlet and turn it on/off when needed?
Or do you close the valve from the water source and outlet when not in use?

2. Do you also mount a valve on the waste water outlet and close it when not in use? (so that nothing gets inside the unit)
Or is this not really needed?

Obsessed Reefer · Sep 10, 2020

I have a small AquaticLife RO Buddie system. When not in use I turn the valve off from the cold water line. I also have my RO line split before the DI chamber, and have a valve there so I can flush the line before going to DI. Then I have the last valve at the end of the output line. My waste line runs into the same drain as my washing machine so I can’t put a valve there.

Opus · Sep 10, 2020

Levinson said:
I've just installed RODI unit for the first time and it's working great, thanks to some of the advices from r2r.
I've got some questions which may sound stupid but thought it wouldn't hurt to ask. I didn't have much luck finding the answers online.

1. Do you keep the RODI unit pressurised (with the valve from the water source kept open) and mount a valve on the outlet and turn it on/off when needed?
Or do you close the valve from the water source and outlet when not in use?

2. Do you also mount a valve on the waste water outlet and close it when not in use? (so that nothing gets inside the unit)
Or is this not really needed?

You want to shut it off before the membrane. If you don't then you will have to shut off both of the lines coming out of the RO membrane. It is up to you on where you do it. I have a mur-lok ball valve fitting in the line before my filter that I use to turn the water on/off. Just easier for me than doing it at the source.