Display shows ERR 04; unit may stay in regeneration or fail to start regeneration at scheduled time.

Safety: Shut off water to the softener and relieve pressure by opening a downstream faucet before removing any meter components.

• Check meter cable: Inspect the cable from the turbine/meter body to the control board. Look for cuts, kinks, or loose connectors. Reseat both ends.
• Clean turbine: Remove the meter housing or turbine insert (depending on your Pentair valve design). Rinse under clean water and remove iron, sand, or scale deposits that may prevent spinning.
• Spin test: Gently blow through the meter port or spin the turbine with a small tool. It should rotate freely without sticking.
• Control setting: Enter the installer menu and verify the correct meter type and size are programmed for your Pentair softener (e.g., 3/4" turbine, 1" turbine). Incorrect settings can trigger flow errors.
• Replace sensor: If the turbine is clean and spins freely but the control still does not register flow (check diagnostics screen for flow rate while running water), replace the Pentair turbine flow meter assembly.
• Test: Restore water, check for leaks, and run water at a faucet while viewing the flow rate on the display. Confirm ERR 04 is cleared.