how to Connect RO line to PEX?

SynDen

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#1
So part of my big tank has a cooling system, which is 1/2" pex line connected to a faucet, does a big coil in the tank, and dumps into my drip system for the front yard. I want to connect my Ro waste line to this, so that it too will dump to the yard when I make fresh water.

Problem is I cant seem to find a way to connect the 1/4" RO tube to the 1/2" Pex line. I have several reducing adapters but the issue is that PEX line is measured differently then a RO tube. 1/4" pex is quite a bit wider then ro tube and I have yet to find a fitting that will let me connect the 2 together.
Any one ever try to attach their RO to a PEX line, and if so, how did you do it?
 

JuanGutz

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#2
Don’t have a fix for you but just wondering is it going to drop into your front yard during the winter too? And if so are you not afraid of freezes backing up the line?
 

Andrew_bram

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#3
I am not exactly sure of the set up but I connected my ro unit to pex using a shark bite.

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TheRealChrisBrown

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#4
Could you dip the end of the PEX in boiling water for a bit, then push it onto the fitting? then when it cools maybe it would contract enough to seal tightly? But I think I'm thinking it the PEX is smaller than the adapter...you might be saying the PEX is larger.
 

SynDen

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#5
Don’t have a fix for you but just wondering is it going to drop into your front yard during the winter too? And if so are you not afraid of freezes backing up the line?
In winter it will dump to my sink in the basement, which is where it dumps currently

I am not exactly sure of the set up but I connected my ro unit to pex using a shark bite.

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Ya I have several sharkbite adapters, plus many john guest push fittings as well, and I cant get any to fit both yet. If you get a chance, mind looking at the connection?

Could you dip the end of the PEX in boiling water for a bit, then push it onto the fitting? then when it cools maybe it would contract enough to seal tightly? But I think I'm thinking it the PEX is smaller than the adapter...you might be saying the PEX is larger.
That might work if the size different wasn't so much. But RO 1/4" will fit inside PEX 1/4". RO tubing is measured by outer diameter, and pex measured by inner diameter, so pex size is quite a bit larger
 

whyamisofly

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#6
I used Sharkbite as well - will grab a picture when I get home.
 

SynDen

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#9
ah good idea. didnt think of using the faucet adapter which would have standard threading. thanks
 

whyamisofly

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#11
Mine is an inline T, with the 1/4 connection in the middle.
 
#12
Hi Angel -

Can you explain how you have things set up to feed to your backyard drip system? I've been wanting to do that for a long time with my RO/DI waste line plus the water I change out of my freshwater tanks.


Thanks!
Larry
 

SynDen

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#13
Hi Angel -

Can you explain how you have things set up to feed to your backyard drip system? I've been wanting to do that for a long time with my RO/DI waste line plus the water I change out of my freshwater tanks.


Thanks!
Larry
Sure. Initial connection for the cooling system is just tee'd into the cold water line for the washing machine with 1/2" pex
View attachment 13427
The line for that coils around in sump and then is connected to a 1/2" poly line coming in from outside with a shark bite and pvc adapter. That line runs outside and is connected to the main line for the drip system. Outside it goes through a pressure regulator before attaching to the main sprinkler line. A few valves in place so I can change whether I want to water the front or the back.

The RO line will tee in just before the poly connection to the outside. A few check valves will ensure it flows outside View attachment 13428

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whyamisofly

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#14

whyamisofly

Tang
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#16
Oops, didn't realize it posted the picture sideways. The piece coming out the right is 1/4 RO tubing, the top and bottom are 1/2" CPVC.
 

SynDen

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#17
Oops, didn't realize it posted the picture sideways. The piece coming out the right is 1/4 RO tubing, the top and bottom are 1/2" CPVC.
kewl, thanks. will have to see if I can find that fitting
 

whyamisofly

Tang
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#18
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