Xylem Flygt 2250, Installation, Operation And Maintenance Manual

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1. Check that the impeller can rotate easily.
2. Turn the adjusting nuts down to the bottom of the studs.
3. Press the diffuser against the impeller.
4. Tighten the adjusting nuts so that they lie flush against the diffuser.
5. Back off all adjusting nuts another half turn (counterclockwise).
The impeller clearance should be minimal when the impeller is tightened. Use the
adjusting washers to adjust the clearance.
6. Place washers and nuts on the studs. Tighten the nuts evenly all around.
7. Check that the impeller can rotate easily.
8. Install the strainer.
Replace the diffuser
1. Remove the diffuser:
a) Remove the impeller, see Remove the impeller (page 28).
b) Remove the sleeves.
c) Remove the nuts and washers.
d) Remove the diffuser.
WS001831A
2. Install the diffuser:
a) Fit the sleeves.
b) Fasten the diffuser in place with the nuts and washers.
Tightening torque: 160–200 Nm (120–150 ft-lbs)
c) For further instructions, see Install the impeller (page 28).
Replace the upper diffuser
Remove the lower diffuser, see Replace the diffuser (page 30).
1. Remove the upper diffuser:
a) Unscrew the nuts and remove the washers.
b) Pull off the wear protection and the upper diffuser.
c) Remove the O-ring.
WS001834A
2. Clean the O-ring and its sealing surfaces carefully prior to installing the O-ring.
Maintenance
30 Flygt 2250 Installation, Operation, and Maintenance Manual