• Ensure the e e e e V V V V a a a a p p p p I I I I n n n n f f f f l l l l o o o o w w w w flow reading does not drop more than 10 ml from the value

recorded in step 11 as the M M M M i i i i x x x x e e e e r r r r O O O O u u u u t t t t l l l l e e e e t t t t pressure increases 5 to 10 kPa above the

M M M M i i i i x x x x e e e e r r r r O O O O u u u u t t t t l l l l e e e e t t t t pressure recorded in step 11.

14. When the e e e e V V V V a a a a p p p p I I I I n n n n f f f f l l l l o o o o w w w w flow reading approximately matches the e e e e V V V V a a a a p p p p O O O O u u u u t t t t f f f f l l l l o o o o w w w w flow

reading (± 20 ml), record the M M M M i i i i x x x x e e e e r r r r O O O O u u u u t t t t l l l l e e e e t t t t pressure.

15.To calculate the leak rate of the Backpressure Valve, subtract the e e e e V V V V a a a a p p p p I I I I n n n n f f f f l l l l o o o o w w w w flow

reading recorded in step 8 from the e e e e V V V V a a a a p p p p I I I I n n n n f f f f l l l l o o o o w w w w flow reading recorded in step 11.

• Replace the Backpressure Valve if the flow rate difference

is greater than 10 ml/min.

16.To calculate the pressure created by the Backpressure Valve, subtract Mixer Outlet

pressure reading recorded in step 6 from the Mixer Outlet pressure reading

recorded in step 14.

• Replace the Backpressure Valve if the pressure created by the backpressure valve

is less than 24 kPa.

Note: A typical backpressure created by the Backpressure Valve

is between 30 kPa and 50 kPa.

Step 6

Mixer Outlet (kPa)