Direction Of Rotation; Priming; Startup - Grundfos LSV Serie Montage- Und Betriebsanleitung

4.2.4 Direction of rotation

Check the direction of rotation in the following way:
1. Disconnect the two coupling halves between
pump and motor.
2. Make sure that the motor shaft can turn freely.
3. Start the motor briefly to check the direction of
rotation. The correct direction of rotation is
indicated by the arrows on the pump casing.
The direction of rotation of the pump is not
always the same as the flow direction.
4. If the direction of rotation is wrong, correct it by
interchanging two phases on the motor.
DANGER
Electric shock
Death or serious personal injury
- Before interchanging two phases, make
sure that the power supply has been
switched off and that it cannot be
accidentally switched on.
5. Check the direction of rotation again.
6. Reassemble the coupling and the guards.

4.3 Priming

LSV pumps are non-self-priming and must be
completely primed, that is filled with liquid, before
starting.
The pump must not run dry. Dry-running
will cause serious damage to the stuffing
boxes, shaft seals, wear rings and shaft
sleeves.
If the pump will be operating with a positive inlet
pressure, prime it by opening the inlet valve and
allowing liquid to enter the pump housing. Open the
vents at the top of the upper pump housing and the
top of each inlet dome, and make sure that all air is
forced out of the pump by the liquid before closing
the vents.
Rotate the shaft by hand while priming and venting to
free entrapped air from the impeller passageways.
If the pump will be operating with a suction lift,
priming must be accomplished by other methods.
Use foot valves, ejectors or vacuum pumps, or fill the
pump housing and inlet line manually with liquid.
Never run the pump dry in the hope that it
will prime itself. The result will be serious
damage to the shaft seals, pump wear
rings and shaft sleeves.
14

4.4 Startup

1. Start the pump.
2. Vent the pump during startup by loosening the
vent screw until a steady flow of liquid runs out of
the vent hole.
WARNING
Hot or cold surface
Death or serious personal injury
- Pay attention to the direction of the vent
hole, and ensure that the escaping
water does not cause injury to persons
or damage to the motor or other
components.
- In hot-water installations, pay special
attention to the risk of injury caused by
scalding hot water and hot surfaces.
- In cold-liquid installations, pay special
attention to the risk of injury caused by
cold liquids and cold surfaces.
3. When the pipe system has been filled with liquid,
slowly open the outlet isolating valve or throttle
valve until it is completely open. Ensure that the
differential pressure developed by the pump is
within the performance range of the pump and/or
close to the designed duty point. Throttle the
outlet isolating valve or reduce the speed of the
pump if the flow exceeds the rated performance
range or the differential pressure is lower than
the rated performance range.
4. Adjust the stuffing box gland (stuffing boxes
only). With the pump running, tighten the stuffing
box gland to allow a leakage of 40-60 drops per
minute. This is required for shaft-sleeve
lubrication. Tighten the stuffing box gland evenly
to provide uniform compression on the packing
rings. After initial startup, additional packing rings
and adjustment may be required until the packing
rings are properly seated.
5. Ensure the pump unit is operating smoothly
without abnormal noise, vibration or overheating.
Do not allow a stuffing box to run dry, and
do not overtighten the stuffing box gland to
eliminate leaking as the shaft sleeve will
become damaged.