GE Datex-Ohmeda Aisys Carestation Reference Manual page 283

Note
Scenario Pressure
Response
1 Pressure
sharply
increases
2 Pressure
sharply
increases
3 Pressure
does not
increase
4 Pressure
sharply
increases
5 Pressure
does not
increase
M1046983 04/08
7. Disconnect the Mixer to eVap "Inlet" tubing from the back of the eVap.
Ensure Inflow meter reading is zero. If non-zero, wait for the system to perform an Auto-
zero cycle. When the eVap auto-zeros, an audible click can be heard and the LED
(CR17) next to the zero valve connector temporally illuminates.
8. Connect the Calibration Gas Regulator
output to the ADU Test Cassette port
labeled "Inlet Check".
9. Observe the Inflow flow reading and the
pressure on the pressure measurement
device. After 20 seconds, record the
readings for the flow and pressure.
10.Determine the Pass/Fail disposition of the valve using the table below:
Inflow Reading Pass / Fail
(ml/min)
0 flow Pass
Negative flow less Pass
than
4 ml/min
Negative flow Fail
4 ml/min or more
Negative flow Possible test error
4 ml/min or more or inflow meter not
zeroed
0 flow Possible test error
or test set-up leak
11.Repeat steps 5 through 10 three times (reconnecting the Mixer to eVap "inlet" tubing
to the back of the eVap).
12.If any of the three tests results indicate "Fail", replace the Inflow Check Valve.
13.Re-connect all the machine tubing and re-install the dashboard.
14.Perform a post service checkout on the machine.
7 Troubleshooting
Comments
Inflow Check Valve is functioning properly.
Inflow Check Valve is acceptable
(leak below limit of 5 ml/min).
Inflow Check Valve is leaking.
• Replace Inflow Check Valve.
Wait for Inflow meter auto zero cycle and
re-record flow.
• If flow goes to 0 (or less than -4 ml/min),
Inflow Check Valve is acceptable.
• If negative flow (greater than –4 ml/min)
persists, troubleshoot for test pressure
reading error or flowmeter reading error.
Repeat test as needed.
Possible adjustment of restrictor or leak in
tubing. Check test setup and re-test.
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