KAH Operation & Maintenance Guide
Page: 41 of 88
Krueger | 1401 N Plano Rd | Richardson, TX 75081 | 972.680.9136 | [email protected] | www.krueger-hvac.com
SECTION 3 - MAINTENANCE (CONTINUED)
FIGURE 41 - SHEAVE ANGULAR
MISALIGNMENT
ANGULAR MISALIGNMENT
FIGURE 42 - MOTOR BASE
LOWERED
MOTOR
SHEAVE
BE
LT
FAN
SHEAVE
MOTOR
PLENUM
FAN
BELT REPLACEMENT TENSIONING AND SHEAVE ALIGNMENT
FOR TOP MOUNT
Use the following instructions to align the sheaves on the motor base:
1. To remove the old belt, loosen the mounting hardware on the drive side
of the motor base. The drive side has two adjusting screws. Do not
increase the left side more than 1/2” before increasing the right side.
2. Remove the tension from the belt on the lower drive side, using the
adjustment screws as shown in Figure 41 (right).
3. After the tension is removed from the belt, loosen the mounting
hardware on the opposite drive side of the base.
4. Continue to lower both ends of the base until the belts can be removed
as shown in Figure 42 (right).
5. After the sheaves are checked for parallel alignment as shown in Sheet
1, place the belts on the sheaves.
6. To take the slack out of the belt(s), start raising the base in 1/2”
increments, using the adjustment screws on both ends.
7. As the belts start to tighten, check for parallel misalignment by placing
a straight edge across the outer face of the sheaves as shown in Figure
43 on the next page. The straight edge should be long enough to extend
past both sheaves.
8. If the sheaves are misaligned as shown in Figure 41 (right), raise the
opposite drive side.
9. Continue to tighten the belt(s), using the drive side the adjusting screws.
10. If the sheaves are still misaligned as shown in Figure 42 (right), make
sure the belt tension is correct, then secure the mounting hardware on
the drive side.
11. If the sheaves are still misaligned as shown in Figure 42 (right), make
sure the belt tension is correct, then lower the drive side of the base to
remove to remove the belt tension.
12. Loosen the mounting hardware on the opposite drive side, and raise or
lower the base accordingly, and repeat Steps 6-10.
13. Mark the position of the base’s opposite drive side mounting hardware
before lowering the base, which may help determine where to secure
the hardware the next time the belt is replaced.
14. Reinstall the belt.
NOTE -
As the belt tension increases, the opposite drive side of the
belt will rise. Make sure the mounting hardware on the opposite
drive side is secure.