RO-45 Flow Rate Test

(Test flow rate at Point: 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.

Test Point A: Check feed pressure to Stage-1

  • See Fig 2, 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.
  • Remove the RED feed line going into the stage-1 Pre-filter at point A.
  • If your input water pressure is above 50-60psi, you should see input water shooting out forcefully. Not just a good flow.
  • Fill a 1 gallon jug from the RED line. Time it. Record timing for point A.
  • If your feed pressure to RO is really 55-60psi, it should take only 48-50 seconds to fill the 1 gallon jug.
  • If it takes longer than 1.5 minutes (90 seconds) to get 1 gallon --> the pressure to RO is under 20psi.

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

  • See Fig 2, 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. Record timing for point D.
  • If your input water at point A can fill 1 gallon in 48- 50 seconds --> the flow speed at point D should be about the same, or just slightly slower.
  • If it takes much longer then 48-50 seconds to get 1 gallon from point D --> your 3 pre-filters are clogged.

Test Point C3: Check Pure Water Speed - After Membrane

  • See Fig 2, at point C3: 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 permete pump at point C3.
  • Fill an 8 oz glass from this line. Time it. Record timing for point C3.
  • At 55-60psi, your RO-Perm system should take 125 - 150 seconds to make 8oz pure water.
  • If it takes much longer than 4 minutes for 8oz of water--> The membrane might be depleted and needs to be replaced. Only a TDS test at this point would verify.

Test Point F: Measure Pure Water Speed - After ASO

  • See Fig 2 Point F. Here the pure water just passed thru the ASO, ready to enter tank. Check the flow speed here. This will tell if the ASO is good, or clogged.
  • Remove the CLEAR line from the T-fitting at point F.
  • Fill an 8oz glass from this line. Time it. Record timing for point F.
  • At 55-60psi, your RO-90 system should take 120- 150seconds to make 8oz pure water.
  • If it takes much longer than 120- 150seconds for 8 oz --> The ASO is partially clogged, slowing down the pure water output flow.

* * * End of Test * * *

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

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