Grundfos BMPX Serie Notice D'installation Et D'entretien page 14

18.3 X-Changer
Warning
Before starting work on the X-Changer, make sure that the electricity supply has been switched off and that it cannot
be accidentally switched on.
Fault Cause
1. Excessive sound a) The X-Changer operates above rated flow
pressure levels.
b) The X-Changer operates with little or no
c) Air in system.
2. Excessively high a) The BMP hp feed pump is operating at too
recovery in the SWRO
system.
b) Excessively high recovery in the SWRO
c) Low-pressure flow is less than high-pressure
3. High salinity in high- a) Unbalanced system.
pressure sea-water
b) A jammed or stalled rotor short-circuits high-
feed stream.
4. Low-pressure flow is a) Operating the X-Changer below rated flow
less than high-pressure
flow resulting in mixing
and high SWRO feed
b) Malfunctioning and/or stalled BM hp
water salinity.
5. Stalled rotor a) Operating system above rated pressure or
(no audible rotation).
b) Foreign debris or particles lodged in device.
c) System is not properly flow-balanced.
6. Low reject flow. a) Excessive pressure losses through the
b) Malfunctioning and/or stalled BM hp
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rates on low-pressure side, high-pressure
side or both.
back-pressure.
high a flow rate.
system.
flow resulting in mixing and high feed water
salinity.
pressure reject water with high-pressure
feed water. No exchange occurs; no audible
rotation.
rate results in low rotor rotation and
increased mixing.
circulation pump.
below rated flow capacity.
SWRO system.
circulation pump.
Remedy
Immediately reduce flow rate by adjustment of the
BM hp circulation pump and control valve (V2). Balance
the system as described in section 11.6 Balancing the
X-Changer.
Increase the back-pressure by adjusting the low-
pressure reject-water valve (V3). Re-balance the
system as described in section 11.6 Balancing the X-
Changer.
Vent the system.
Verify that the main BMP hp feed pump flow rate does
not exceed the membrane array production capacity for
a given temperature, salinity and fouling factor.
Increase and balance flows through the X-Changer.
Do not exceed recommended maximum flow rates.
See section 11.6 Balancing the X-Changer.
See section 11.6 Balancing the X-Changer.
See fault number 5.
Increase and balance flows through the X-Changer.
Do not exceed recommended maximum flow rates.
See section 11.6 Balancing the X-Changer.
Check BM hp circulation pump rotation, operation, flow
rates and pressures.
See section 11.6 Balancing the X-Changer.
Contact Grundfos Service.
See section 11.6 Balancing the X-Changer.
Contact Grundfos.
Check operation, flow rates and pressures of the BM hp
circulation pump.