Radial gap, overlap and wheel alignment – Greenheck Housed Plenum Array , Plug and Plenum Fans (475405) User Manual
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8
Housed Plenum Array, Plug and Plenum
Unit
Size
PLG
Inlet Cone to Backplate
APM, APH
Wheel Cone to Inlet Cone
HPA
Wheel Cone to Inlet Cone
A Dimension*
± Tolerance (in.)
A Dimension*
± Tolerance (mm)
Offset
± Tolerance (in.)
Offset
± Tolerance (mm)
Offset
± Tolerance (in.)
Offset
± Tolerance (mm)
7
1
3
⁄
16
± 1/8
30
± 3
8
2
3
⁄
16
± 1/8
36
± 3
9
3
3
⁄
16
± 1/8
81
± 3
10
3
7
⁄
16
± 1/8
87
± 3
12
4
± 1/8
102
± 3
1/8
± 1/16
3
± 1.5
7/16
± 1/16
11
± 1.5
13
4
7
⁄
16
± 1/8
113
± 3
15
5
± 1/8
127
± 3
1/8
± 1/16
3
± 1.5
7/16
± 1/16
11
± 1.5
16
5
7
⁄
16
± 1/8
138
± 3
3/16
± 1/16
5
± 1.5
7/16
± 1/16
11
± 1.5
18
6
3
⁄
8
± 1/8
162
± 3
3/16
± 1/16
5
± 1.5
7/16
± 1/16
11
± 1.5
20
7
± 3/16
178
± 5
1/4
± 1/16
6
± 1.5
7/16
± 1/16
11
± 1.5
22
7
13
⁄
16
± 3/16
198
± 5
1/4
± 1/16
6
± 1.5
7/16
± 1/16
11
± 1.5
24
8
5
⁄
8
± 1/4
219
± 6
5/16
± 1/16
8
± 1.5
7/16
± 1/16
11
± 1.5
27
9
7
⁄
16
± 1/4
240
± 6
3/8
± 1/16
9.5
± 1.5
9/16
± 1/8
14
± 1.5
30
10
9
⁄
16
± 3/8
268
± 10
3/8
± 1/16
9.5
± 1.5
9/16
± 1/8
14
± 1.5
33
11
7
⁄
16
± 3/8
291
± 10
7/16
± 1/16
11
± 1.5
9/16
± 1/8
14
± 1.5
36
12
3
⁄
4
± 3/8
324
± 10
7/16
± 1/8
11
± 3
9/16
± 1/8
14
± 3
40
14
3
⁄
16
± 3/8
360
± 10
1/2
± 1/8
13
± 3
44
15
9
⁄
16
± 3/8
395
± 10
9/16
± 1/8
14
± 3
49
17
1
⁄
8
± 1/2
435
± 13
5/8
± 1/8
16
± 3
54
18
13
⁄
16
± 1/2
478
± 13
5/8
± 1/8
16
± 3
60
20
15
⁄
16
± 1/2
532
± 13
3/4
± 1/8
19
± 3
66
22
7
⁄
8
± 1/2
581
± 13
7/8
± 1/8
22
± 3
73
25
1
⁄
2
± 1/2
648
± 13
1
± 1/8
25
± 3
*A dimension does not apply to partial width wheels.
Radial Gap, Overlap and Wheel Alignment
Efficient fan performance can be maintained by having the correct radial gap, overlap and wheel alignment. These
items should be checked after the fan has been in operation for 24 hours and before start-up after the unit has been
serviced.
Radial Gap (model PLG) is adjusted by loosening the
inlet cone bolts and centering the cone/ring on the
wheel. If additional adjustment is required to maintain
a constant radial gap, loosening the bearing bolts
and centering the wheel is acceptable as a secondary
option.
Overlap, or offset, (model APM, APH, HPA) is adjusted
by loosening the wheel hub from the shaft and moving
the wheel to the desired position along the shaft. The
transition between the inlet cone and wheel should be
as shown; there is a smooth feel to the profile when
moving from one component to the other.
PLG
Radial
Gap
Overlap
A
Inlet
Cone
Wheel
APM, APH, HPA
Inlet
Cone
Wheel
Offset