COMBUSTION-AIR BLOWERS (48P ONLY)
Clean periodically to assure proper airflow and heating efficiency. Inspect blower wheel every fall and periodically during heating season. For the first heating season, inspect blower wheel bi-monthly to determine proper cleaning frequency.
To inspect blower wheel:
SUPPLY FAN AND POWER EXHAUST MOTOR PLATE
Adjust using a 15/16-in. wrench on the adjusting bolts:
IMPORTANT: When installing or replacing belts, always use a complete set of new, matched belts to prevent potential vibration problems. Mixing belts often results in premature breakage of the new belts.
BELT INSTALLATION AND TENSIONING:
NOTE: Check the tension at least twice during the first day of operation, as there is normally a rapid decrease in tension until the belts have run in. Check tension periodically thereafter and keep it at the recommended tension.
With the correct belt tension, belts may slip and squeal momentarily on start-up. This slippage is normal and disappears after wheel reaches operating speed. Excessive belt tension shortens belt life and may cause bearing and shaft damage.
For proper belt life, the motor and fan pulleys must be properly aligned. To check, first turn off unit power. Place a straightedge against the motor and fan pulleys. See Fig. 52. If the pulleys are properly aligned, the straightedge should be parallel to the belts.
If they are not parallel, check that the motor shaft and fan shaft are parallel. If they are not, adjust the motor plate adjusting bolts until they are.
After verifying that the shafts are parallel:
INSTALLING REPLACEMENT MOTOR PULLEY (SUPPLY FAN ONLY)
To install a field-supplied replacement pulley:
CONDENSER FAN ADJUSTMENT (ALL UNITS EXCEPT SIZE 035)
Source: Carrier (www.shareddocs.com)