Troubleshoot Guide: Slow Output & Slow Shut Off

RO-90 (Test flow speed: A, D, C3, F)

To determine why your RO's output is slower than normal, we need to test the input water pressure, and the water's output speed at different points on the RO system. Please do the test steps below, and let us know your test results.

See RO-90 Head Diagram to locate the testing points on the system.

Test Point A:Check feed pressure to RO

  • See Diagram, at point A: We need to test your input water pressure by measuring how long it takes to fill 1 gallon of water from the feed line. Do as follows:
  • Remove the RED feed line going into the stage-1 Pre-filter at point A.
  • If your input water pressure is above 40-50psi, you should see input water shooting out quite forcefully. Not just a good flow.
  • Fill a 1 gallon jug from the RED line. Time it to see how many seconds it takes to fill 1 gallon. Record timing for point A.
  • If your feed pressure to RO is really 40-50 psi, it should take only 50- 57 seconds to fill the 1 gallon jug.

Test Point D:Check Input Pressure to Membrane - After 3 Prefilters

  • See Diagram, at point D: Here the input water just passed thru stages 1, 2, 3 prefitlers. It is entering the Membrane at point D. We want to check the flow speed at this point. It will tell if the 3 pre-filters are good, or clogged.
  • Remove the RED line from the membrane's cap at point D.
  • Fill a 1 gallon jug from the RED line. Time it to see how many seconds it takes to fill 1 gallon. Record timing for point D.
  • If your input water at point A can fill 1 gallon in 50 - 57 seconds --> the flow speed at point D should be about the same, or just slightly slower.

Test Point C3:Check Pure Water Speed from Membrane

  • See Diagram, at point C3: Here the PURE water just comes out of the membrane, reaching up to the ASO at point C3. We want to check the flow speed at this point. It will tell how fast the membrane is making water. This also confirms if the membrane is good, or clogged.
  • Remove the CLEAR line from the pump's C3 port (lower right hand port).
  • Fill an 8 oz glass from this line. Time it to see how many minutes it takes to fill 8 oz. Record time for C3 port.
  • At 40-50psi, your RO-90 system should take 1- 1.5 minutes to make 8oz pure water.

Test Point F:Measure Pure Water Speed after the ASO

  • See Diagram at point F. Here the pure water just passed thru the pump, ready to enter the tank. Check the flow speed here. This will tell if the pump is good, or clogged.
  • Remove the CLEAR line from the T-fitting at point F.
  • Fill an 8oz glass from this line. Time it to see how many minutes it takes to fill 8 oz. Record timing for point F.
  • At 55-60psi, your RO-90 system should take 1 - 1.5 minutes to make 8oz pure water.

Give us your test results (flow speed) for points A, D, C3 and F.

* * * End of Test * * *

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