Reverse osmosis water treatment system with stainless tanks and pumps

RO system: slow flow or no water at the faucet

Slow RO water comes from a low tank air charge or failed bladder, clogged pre-filters, a fouled membrane, low feed pressure, or a clogged post-filter. A timed flow test splits filter/pressure problems from membrane problems.

Cross-checked ~45 min moderateBrands: All

Before you start

Close the feed valve before opening housings
Expect some water when removing filters

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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