110
McQuay IM 987
Maintenance
Figure 119: Return Fan Assembly
Supply Fan Wheel-to-Funnel Alignment
If the unit is equipped with an airfoil or backward curved
supply fan, the fan wheel-to-funnel alignment must be as
shown in
Figure 120
,
Figure 121
,
Figure 123
, and
Figure 124
to obtain proper air delivery and operating clearance. If
necessary, adjustments are made as follows:
1
Verify that the fan shaft has not moved in its bearings.
2
Loosen the fan hub setscrews and move the wheel(s)
along the shaft as necessary to obtain the correct
dimension shown in Table 32, Table 33, and Table 34.
3
Retighten the setscrews to the torque specification given
in Table 31 on page 122. Tighten the setscrews over the
keyway first; tighten those at 90 degrees to the keyway
last.
4
Verify that the radial clearance around the fan is uniform.
Radial clearance can be adjusted by slightly loosening
the funnel hold-down fasteners, shifting the funnel as
required, and retightening the fasteners.
Figure 120: 20" DWDI Airfoil Wheel-to-Funnel
Figure 121: 24" DWDI backward curved wheel-to-funnel
(036C, 040C)
Figure 122: 27 to 40" DWDI Airfoil Wheel-to-Funnel
Alignment
Figure 123: 40" SWSI Airfoil Wheel-to-Funnel Alignment
Figure 124: 44" and 49"SWSI Airfoil Wheel-to-Funnel
Alignment
Experience in the field has shown that R-407C systems can be
“topped off” after a leak has been repaired and operate
normally. There is no need, except in the case of a critically
charged systems, to replace the entire charge after a leak has
been repaired.
U p p e r B e a r i n g
F a n W h e e l
F a n S h a f t
S u p p o r t
L o w e r
B e a r i n g
F a n S h a f t
F u n n e l
. 2 5 "
. 2 5 "
W h e e l
W h e e l
. 1 8 "
F u n n e l
9 . 3 1 "
9 . 3 1 "
C L
F a n
. 1 8 "
Table 24: 27 to 40" DWDI Airfoil Wheel-to-Funnel
Relationship
Wheel-to-funnel relationship (in inches)
Wheel diameter (inches)
“A” +0.3/ — 0.0
27
9.9 (246 mm)
30
10.6 (269 mm)
33
11.7 (297 mm)
36
13.1 (333 mm)
40
14.5 (368 mm0
Table 25: SWSI Airfoil Wheel-to-Funnel Relationship
Wheel-to-funnel relationship (in inches)
Wheel diameter
“A”
40
0.62
Table 26: 44" and 49"SWSI airfoil wheel-to-funnel
Relationship
Wheel-to-funnel relationship (in inches)
Wheel diameter
“A”
44
16.21
49
17.81
W h e e l
F u n n e l
A
W h e e l
F u n n e l
A
Содержание RAH 047C
Страница 70: ...70 McQuay IM 987 Wiring Diagrams Figure 78 VAV Control Inputs Schematic continues on next page ...
Страница 71: ...McQuay IM 987 71 Wiring Diagrams Figure 79 VAV Control Inputs Continued Schematic continues on previous page ...
Страница 74: ...74 McQuay IM 987 Wiring Diagrams Figure 82 VFD Control SAF and RAF Schematic continues on next page ...
Страница 104: ...104 McQuay IM 987 Final Control Settings Figure 117 Keypad Accessible Menu Structure ...
Страница 105: ...McQuay IM 987 105 Final Control Settings Figure 118 Keypad Accessible Menu Structure Continued ...
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