Figure 32 - Fan With The Hub On The Top And Ret On The Bottom; Figure 33 - Bushing Mount Location; Figure 34 - Ret With Pin In Groove 4; Figure 35 - Fan Hub And Ret Castings - AAON RN Series Installation Operation & Maintenance

Step 2: Maintain the balance of fan
Mark the HUB/RET castings across a single
joint, so the fan can be reassembled in the
same orientation.
Mark the location of any balancing weight.
Balancing weight will be on the outer bolt
circle, in the form of washers, and/or longer
bolts, or an additional balancing nut.
Number the blades and blade sockets, so that
they can be replaced into their original
positions.
Figure 32 - Fan with the HUB on the Top
and RET on the Bottom
Step 3: Determine the direction of rotation
Right, R, is clockwise when facing the
discharge side of the fan and Left, L, is
counterclockwise when facing the discharge
side of the fan.
Step 4: Determine the bushing mount
location
The bushing mount is the center section of the
hub through which the fan is mounted to the
shaft, and typically contains either setscrews
or a center-tapered hole where the bushing
inserts.
Location A is with the bushing mount on air
inlet side of the fan.
Location B is with the bushing mount on air
discharge side of the fan.
Bushing Step 5: Determine the pin location groove
Mount
Disassemble fan on a flat surface and note in
which groove the pin is located.
Step 6: Determine whether the pin is in the
HUB or RET

Figure 35 - Fan HUB and RET Castings

Bushing
A
Bushing
Mount

Figure 33 - Bushing Mount Location

1 2 3 4

Figure 34 - RET with Pin in Groove 4

Bushing
B
53