IM 738-2
97
Unit Options:
Propeller Exhaust Fan Option
Figure 101. Belt adjustment
Figure 102. Drive pulley alignment
Figure 103. Propeller exhaust fan replacement parts list
B e l t S p a n
D e f l e c t i o n = B e l t S p a n
6 4
e n t e r l i n e s
m u s t c o i n c i d e
M u s t b e
p a r a l l e l
M u s t b e
p a r a l l e l
A d j u s t a b l e
S h e a v e
M o t o r
B e a r i n g
Table 24: Propeller exhaust fan troubleshooting
Problem
Cause
Corrective Action
Reduced
Airflow
System resistance is too
high.
Check backdraft dampers for proper operation. Remove obstructions in ductwork. Clean dirty filters.
Check for adequate supply for air exhaust fans or exhaust air for supply fans.
Unit running backwards.
See “Prestarting Checks” on page 96
Fan speed too low.
Increase fan speed
Excessive dirt on propeller. Clean propeller
Excessive
Noise
Bearings
Tighten bearing collars and setscrews. Lubricate bearings. Replace defective bearings.
V-Belt drive
Tighten pulleys on motor shaft and fan shaft. Adjust belt tension. Align pulleys. Replace worn belts or pulleys.
Excessive vibration
Clean dirt build-up from propeller. Check all setscrews and fasteners for tightness. Check for worn bearing.
Correct propeller imbalance. Check for loose dampers, guards or ductwork.
Defective motor
Replace motor.
9
8
7
1 0
6
5
4
1
2
3
1 . F a n pa n e l
2 . P r o p e l l e r
3 . D r i v e fr a m e
ch a n n e l ( 2 )
4 . M o to r pl a te
5 . M o to r
6 . M o to r pu l l e y
7 . S h a ft pu l l e y
8 . F a n sh a ft
9 . B e a r i n g s
1 0. B e l t
1 1. B e a r i n g pl a te
11
Summary of Contents for RDT-135c
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