Daikin RDT-135c Installation And Maintenance Manual page 99

Figure 101. Belt adjustment
Table 24: Propeller exhaust fan troubleshooting
Problem Cause
System resistance is too
high.
Reduced
Unit running backwards.
Airflow
Fan speed too low.
Excessive dirt on propeller. Clean propeller
Bearings
V-Belt drive
Excessive
Excessive vibration
Noise
Defective motor
Figure 103. Propeller exhaust fan replacement parts list
IM 738-2
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.
See "Prestarting Checks" on page 96
Increase fan speed
Tighten bearing collars and setscrews. Lubricate bearings. Replace defective bearings.
Tighten pulleys on motor shaft and fan shaft. Adjust belt tension. Align pulleys. Replace worn belts or pulleys.
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.
Replace motor.
1
2
9
8
7
1 0
4
3
6
5
11
Unit Options: Propeller Exhaust Fan Option
Figure 102. Drive pulley alignment
Corrective Action
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
97