Reverse osmosis water treatment system with stainless tanks and pumps

Connecting an under-sink RO system to the refrigerator or ice maker: tee point, tubing, shutoff, pressure and the fridge filter

Tee into the RO's finished (product) water line, not the feed or drain, add a dedicated shutoff on the fridge branch, and run plastic tubing of the size the kit uses to the refrigerator inlet with a service loop. RO delivery pressure is lower than house pressure and drops as a tank empties, while many refrigerators need a minimum inlet pressure, so small/hollow cubes and a slow dispenser are common after the hookup. Bypass the refrigerator's own filter only if the fridge maker allows it (stacking filters cuts pressure further). Do not feed RO water through copper ice maker lines.

Cross-checked ~60 min moderateBrands: All

Before you start

Check for wiring, pipes and ducts before drilling through cabinets or floors
Do not use thread tape on push-fit or compression fittings
Route tubing away from heat, sharp edges and pinch points behind the refrigerator

Diagnostic steps

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