NuAire AIRMOVER DSA Series Installation And Maintenance Manual page 9

Replacement of Parts (continued)
Axial Flow Impellers (continued)
Assemble the impeller to the shaft. On unit size 315
position the impeller as close as possible to the the
position noted previously.
This applies whether the original or a new impeller is
being fitted. Secure the impeller by tightening the two
grubscrews in the boss. On all other sizes fit impeller as
described below. Replacement is the reversal of the
removal procedure. Ensure the impeller can rotate freely
with the overlap as specified in the drawing. Check that it
is concentric with the venturi. If necessary adjust the
overlap and concentricity by moving the impeller along
the shaft or by using the slots in the motor plate.
Removing a taperlocked impeller from
a motor.
From the locking holes of the taperlock (see illustration)
remove one grub screw. Lightly oil the thread and point
and insert it into the jacking hole. Slacken the other grub
screws.
Tighten the screw until the bush is loosened in the hub
and the assembly of impeller and bush can be drawn from
the shaft. Remove the screw and separate the impeller and
bush.
Tighten
grub
screw
Releasing
Taperlock
Locking
Taperlock
Fitting a taperlock impeller to a motor
Making sure that tapered mating surfaces are thoroughly
clean, insert the taperlock bush into the impeller hub.
Line up holes. Lightly oil threads and points of grub
screws and assemble loosely into the locking holes
(see illustration above).
Clean the motor shaft and fit the impeller and bush as one
unit to the shaft in the position noted during removal.
If relevant, makes sure that a key is fitted into the slot in
the shaft. Tighten screws gradually and alternately until
pulled up tight, noting that the bush will nip the shaft first
and then the hub will be slightly drawn onto the shaft.
Fill empty holes with grease to exclude dirt.
Installation and Maintenance AIRMOVER DSA AXIAL UNITS
Remove grub screw
Split
Remove grub screw
Tighten grub screw
Split
Tighten grub screw
Spare Parts
When ordering spare parts please quote the serial
number of the unit, together with the part number, if
quoted below. If not quoted, please fully describe the
part. The serial number will be found on the
identification plate fixed to the unit.
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