I am currently attempting to install a reverse osmosis water filtration system in the cabinet underneath my kitchen sink next to a refrigerator. The system comes with a faucet which appears to get it's water supply from the blue 1/4 inch plastic tubing. I am not too fond of the idea of having a second water faucet on our kitchen sink and would much rather have the reverse osmosis water system feed the refrigerator so that our ice and and water from the fridge are filtered.

I looked underneath my kitchen sink and found that on the main cold water pipe, there is what appears to be a self piercing T-tap and that one of the lines goes through the cabinet and likely behind a dishwasher. I do not see any other water lines leading there besides the hot water line. I'm assuming that the cold water line feeds the dishwasher and there might be another T-tap splitting the water going to the dishwasher and another line that will feed the 1/4 inch water supply line that goes to my refrigerator.

I was wondering would it be possible to just run a much longer blue 1/4 inch tube from the RO system to my refrigerator? (G to H in the below diagram containing the filtered water). I think I would rather just have the filtered water go straight to the refrigerator.

UPDATE: I pulled my refrigerator out and found that the tap on the cold water pipe goes directly to the refrigerator. What would be the best way to connect a 1/4 inch plastic tubing from the filtered water directly to the refrigerator? Is there a way for me to just directly shut off the T-tap on the cold water valve and just wire the 1/4 inch line directly from the end of the water filtration system directly to my refrigerator?

EDIT #2 - I think what would solve my issue is if I could somehow cut the water supply to that line and then use that angle stop valve to feed the RO filter and then use the blue line at the end of my RO filter to be wired directly into my refrigerator.

Is there a way for me to cut the water to braided line with a red line through it and then have the water from the saddle valve travel exclusively through the 1/4 inch plastic line? Or is there a better solution than that? enter image description here

Also, could I just take out that blue 1/4 inch plastic line from the top of the refrigerator even though it is powered by the steel braided hose on the bottom of the refrigerator?

(rear of refrigerator) enter image description here enter image description here

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Cold water tap for refrigerator water dispenser and possibly dishwasher

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Reverse Osmosis diagram

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Top of dishwasher enter image description here

  • What's the ppm of your water supply. Which ions. 240ppm and something like CaSO4 or CaCO3 is OK. Fe is less so. If your pipes are old style iron, you'll be plugging your prefilter constantly. A water softener first might solve this problem as all the ions->NaCl, which is membrane friendly. Commented Apr 21, 2019 at 2:33
  • My house was built in 1990 and there are all copper pipes. We have city water with a ppm of 120 from the tap. We never had any problems with hard water either. Commented Apr 21, 2019 at 2:44
  • You are probably OK to go then. My house is about 90. Galvanized, and even some lead return pipes. The galvanized steel is great for continually breaking of little flake, which clog filters and faucets. Commented Apr 21, 2019 at 5:35

1 Answer 1


enter image description here

Add this to the top og the saddle valve, it will allow you to add the intake line for the RO, then route you RO line to the icemaker.

  • I have this amazon.com/gp/product/B003YKF2JC/… would that work? Also I was wondering, is the saddle valve the yellowish brass looking piece that is tapping into the main cold water valve? Also, If i take out the blue line that is currently routed to my ice maker, wouldn't the water shoot out since I would have one line not connected to anything and another line which is coming out of my RO be the only line connected to the icemaker? Commented Apr 21, 2019 at 3:12
  • Yes according to the reviews/comments, it will work for you. Before you remove any line, turn the saddle valve off, yes it is the one that is tapped in the side of the supply line.It is held in place by the long screws. I mention this just for identification. It will usually take many turn to close off, but that will keep water from shooting out under pressure. When you loosen the silver braided line there will be residual water still left in the line after you close the saddle valve and make sure it is off by going to the icemaker by testing it out. Have a sponge or paper towels handy.
    – Jack
    Commented Apr 21, 2019 at 3:29
  • Thank you, also i was wondering, would I have an issue connecting the 1/4 inch plastic line from the RO filter directly to the refrigerator by taking the old 1/4 inch plastic line out of the refrigerator? I see on the bottom of the refrigerator that there is a steel braided line and when the water dispenser is being used, water is flowing through that steel braided line. Commented Apr 21, 2019 at 3:42
  • I have never tried what you suggest about the direct hook up to the plastic line. I would not try it myself, they set those things up that way for a reason, not that I know what it is, but I would leave it be... Connect it to the braided line with an adapter, it seems the only way to be safe and sure
    – Jack
    Commented Apr 21, 2019 at 3:56
  • Sounds good! Would you happen to know what adapter I would need to connect the 1/4 inch plastic tubing to the steel braided line that leads to the refrigerator? Commented Apr 21, 2019 at 12:30

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