Reverse osmosis water treatment system with stainless tanks and pumps

RO system will not shut off (water always running to drain)

The auto shut-off (ASO) valve closes when tank pressure reaches about two-thirds of feed pressure. If the tank never gets there, or the check valve leaks back, the system keeps running to drain.

Cross-checked ~40 min moderateBrands: All

Before you start

Close the feed before opening fittings

Diagnostic steps

Unlock all 4 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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