Shut off Valve before DI Filter or after?

[regularsizedbrownie]

Hi I am in the process of installing a DI unit to my existing RO system. I was wondering if I should install the ball/shutoff valve before the DI unit (so the housing is not always under pressure) or after the DI unit so the (DI filter stays wet)? Which way do you prefer?

 

[Crabs McJones]

I always thought you put the shut off valve before the entire ro/di unit

 

[exnisstech]

I always thought you put the shut off valve before the entire ro/di unit

This.
If you are trying to isolate the flow between drinking water and di resin it isn't necessary. Just install a tee to your existing membrane output and it can supply the drinking water and di with no need for a shut off. Mine has been this way for years.

 

[gbroadbridge]

Hi I am in the process of installing a DI unit to my existing RO system. I was wondering if I should install the ball/shutoff valve before the DI unit (so the housing is not always under pressure) or after the DI unit so the (DI filter stays wet)? Which way do you prefer?

Depends on your setup.

I have a master valve before the whole unit, however there is a solenoid valve after the DI which controls refilling the ATO reservoir when it is almost empty.

So in my case the system is always under pressure unless I am replacing cartridges.

 

[regularsizedbrownie]

This.
If you are trying to isolate the flow between drinking water and di resin it isn't necessary. Just install a tee to your existing membrane output and it can supply the drinking water and di with no need for a shut off. Mine has been this way for years.

I have a master valve before the entire unit, but since I have a drinking water supply faucet I have a T with a check valve. But I am not going to be producing DI water all the time so was looking to add a shut-off valve for that. I've seen a BRS how-to video add it right before the DI unit so when they turn it off, the DI filter empties itself and it becomes dry. I also saw where they add the shutoff valve after the DI unit, so when they are done with filling their water jugs, and turn off the ball valve the DI unit does not empty itself and the resin stays wet.

Depends on your setup.

I have a master valve before the whole unit, however there is a solenoid valve after the DI which controls refilling the ATO reservoir when it is almost empty.

So in my case the system is always under pressure unless I am replacing cartridges.

Since I don't have a reservoir yet and be filling smaller water jugs I am going with a shutoff valve. I might add it similar to yours after the DI unit so it's just under pressure.

 

[exnisstech]

Not sure how a di canister is going to empty itself with a shut off valve installed before it. There has to be water or air going into the canister in order for the water inside to drain unless there is a vent that will allow air to enter as the water exits. But if BRS says it's so then it must be
Nothing wrong with adding a valve I suppose I just see no need for one.

Edit . I get it now. I have containers with float valves connected to the di output. I guess if your DI output is open then you would have to have one either before or after.

 

[theMeat]

Shut off valve after di, on product line.
Not sure if you have one of these but you’ll need this too

1/4" Auto Shut Off Valve

Installation Instructions 1/4" Automatic shut off valves are used with float valves or pressurized tanks to shut off an RO system. It utilizes the back pressure created by the float valve or pressurized tank to shut off the water supply to the membrane. Without an automatic shut off valve...

www.bulkreefsupply.com

 

[regularsizedbrownie]

Shut off valve after di, on product line.
Not sure if you have one of these but you’ll need this too

1/4" Auto Shut Off Valve

Installation Instructions 1/4" Automatic shut off valves are used with float valves or pressurized tanks to shut off an RO system. It utilizes the back pressure created by the float valve or pressurized tank to shut off the water supply to the membrane. Without an automatic shut off valve...

www.bulkreefsupply.com

I have this auto shut off valve in my system.

Shut off valve after di, on product line.
Not sure if you have one of these but you’ll need this too

1/4" Auto Shut Off Valve

Installation Instructions 1/4" Automatic shut off valves are used with float valves or pressurized tanks to shut off an RO system. It utilizes the back pressure created by the float valve or pressurized tank to shut off the water supply to the membrane. Without an automatic shut off valve...

www.bulkreefsupply.com

Yes, right now i don't have a float valve connected so I have to add a valve and keep an eye on it whenever i fill up the can. So was curious which would be the way. I'm leaning towards putting the valve after the DI so it's easier to turn it off when I'm done.

 

[theMeat]

I have this auto shut off valve in my system.


Yes, right now i don't have a float valve connected so I have to add a valve and keep an eye on it whenever i fill up the can. So was curious which would be the way. I'm leaning towards putting the valve after the DI so it's easier to turn it off when I'm done.

Yeah, put it after di. It goes on the product line that you use to fill. When you shut the valve it takes a minute for the auto shut off to stop the flow of water through the membrane but that’s a good thing. Helps keep membrane clean