1. Look for the rotation button on the filter device and turn it three times in the counterclockwise direction.
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2. Look for the button of the drainage pipe and turn it 90 degrees.
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3. Open the drainage valve at the lower end of the filter device, wait for 20 seconds, and gradually carry out the reverse direction again.
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4. After washing, rotate the button to calibrate.
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5, wait 20 more, turn off the drainage valve, normal use.
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How long does the pre-filter backwash take
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The pre-filter is generally washed once every 15 days or so, each time for 30 seconds, depending on the local water body;