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20901106_EN_MD4_MV2_VARIO_select_V1.0_140818
Fault
Possible cause
Remedy
❑
Loud operating
noises.
➨
Loud outlet noise, out
-
let line open.
✔
Check connections at out-
let. Connect hose or si-
lencer to pump outlet. Be
careful not to cause outlet
overpressure, especially
with condensable vapors.
➨
Diaphragm crack or
diaphragm clamping
disc loose?
✔
Perform maintenance and
replace defective parts.
➨
Ball bearing defective.
or other than above
mentioned causes?
✔
Contact local distributor.
❑
Pump seized.
✔
Contact local distributor.
➨
A service manual with exploded view drawings, spare parts list and
directions for repair is available on request.
+
The service manual is intended for trained service people only.
