Reverse osmosis water treatment system with stainless tanks and pumps

Reverse osmosis (RO) under-sink install

An RO system needs a cold-water feed, a drain saddle on the sink drain above the trap (away from the disposal), a dedicated faucet (often an air-gap faucet where code requires) and the storage tank. Flush the system per the instructions before drinking.

Cross-checked ~120 min moderateBrands: All

Before you start

Shut off the cold water before installing the feed adapter.
Drilling a stone countertop needs the right bit; porcelain sinks chip easily.
Drill only one side of the drain pipe for the saddle.

Diagnostic steps

Unlock all 5 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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