2 4
Function Tests
Service Manual C91 / D91
en
Version 1.0
Measuring flow rate (2)
Procedure (continued):
7. Connect pressure hose to pressure tester.
8. Position measuring beaker underneath
exit tube of pressure tester.
9. Switch on machine.
10. Press coffee button after heatingup.
11. Open valve fully till water begins to flow.
12. Close valve slowly until 12 bar are indi
cated.
The manometer must be observed
continuously and the pressure regu
lated using the valve if necessary.
With increasing temperature the
pressure also increases, if neces
sary readjust the pressure to 12 bar.
13. Perform measurement for approx. 30 sec.
14. There must be at least 60 120 ml water
in the measuring beaker.
Notice:
With a flow of < 60 ml the pump is defective
or there is a leak in the system.
Large fluctuations in the pressure gauge
readings (± 4 bar) during measurement are
indicative of a defective pump.
8
7
10
9
13
12
14
11
