McQuay RDS 802C User Manual

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

McQuay RDS 802C Specifications

General

Brand	McQuay
Model	RDS 802C
Category	Air Handlers
Language	English