Edwards A311-01-985, Instruction Manual

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A311-03-880 Issue A
Page 36 © Edwards Limited 2014. All rights reserved.
Edwards and the Edwards logo are trademarks of Edwards Limited.
Maintenance
Table 15 - Fault finding
Symptom Check Actions
The pump will not start, or seizes
during operation. Has the pump been overloaded? Check the required operating
conditions and specified
performance of the pump (see
Section 2 ).
Has debris or foreign material
entered the pump? Strip down, clean and repair the
pump as necessary.
Is the motor or drive/transmission
system faulty? Check that your motor or drive and
transmission system is operating
correctly, and that it is correctly
fitted to the pump.
Has the pump casing been distorted? Check that the pump is installed on a
level surface (see Section 3.2 ), and
that the maximum loadings on the
inlet/outlet flanges have not been
exceeded (see
Section 3.11 ).
Rectify any problem found, then:
Check the pump casing for
distortion. If the casing is distorted,
contact your supplier or Edwards for
advice.
If the casing is not distorted, check
the rotor clearances. Contact your
supplier or Edwards for advice.
The pump is noisy during operation. Are the rotors touching, or are the
rotors striking the pump casing? Check the rotor clearances and
rotor-compression chamber
clearances. Contact your supplier or
Edwards for advice.
Is gear backlash excessive? Check the gears and replace if
necessary.
Are the gear and/or bearing
clearances incorrect? Check the clearances. Contact your
supplier or Edwards for advice.
Are the rotors unbalanced? Contact your supplier or Edwards for
advice
The pump overheats. Is the inlet filter blocked? Clean or replace the filter.
Is the differential pressure across the
pump too high? Check that your system design
complies with the requirements of
Section 3.2 , and that the pump is
suitable for use in your application.
Is an oil level too high, or has the
incorrect grade of oil been used? Check the oil levels (refer to
Section 5.5 ) or drain the pump and
fill with the correct grade of oil
(refer to
Section 5.7 ).
Are the rotor or rotor/casing
clearances incorrect? Contact your supplier or Edwards for
advice.
Has the cooling-water supply failed
or is the supply inadequate? Check that the cooling-water supply
pipelines are correctly connected to
the pump (see
Section 3.6 ) and that
the supply complies with the
requirements of
Section 2.4 .