NOTES:

1.Torque set screws on blower wheel to 70 in. lbs ± 2 in. lbs.

2.Torque set screw on propeller fan to 15 in. lbs ± 2 in. lbs.

3.Dimensions are in inches.

Fig. 47 Ð Typical Gas Heating Section

3. Slide fan pulley along fan shaft.

4. Make angular alignment by loosening motor from mount- ing plate.

5. Retighten pulley.

Evaporator Fan Service and Replacement

 

1.

Shut off unit power supply.

 

2.

Remove supply-air section panels.

 

3.

Remove belt and blower pulley.

 

4.

Loosen setscrews in blower wheels.

 

5.

Remove locking collars from bearings.

 

6.

Remove shaft.

 

7.

Remove venturi on opposite side of bearing.

 

8.

Lift out wheel.

 

9.

Reverse above procedure to reinstall fan.

Fig. 48 Ð Gas Heat Section Details

10.

Check and adjust belt tension as necessary.

Belt Tension Adjustment Ð To adjust belt tension:

Evaporator Fan Performance Adjustment

(Fig. 49) Ð Fan motor pulleys are designed for speed shown in Table 1 (factory speed setting).

IMPORTANT: Check to ensure that the unit drive matches the duct static pressure using Tables 12-14.

1.Shut off unit power supply.

2.Loosen motor mounting nuts and bolts. See Fig. 50.

3.Loosen fan motor nuts.

4.Turn motor jacking bolts to move motor mounting plate left or right for proper belt tension. A slight bow should be present in the belt on the slack side of the drive while running under full load.

To change fan speeds, change pulleys. To align fan and motor pulleys:

1.Shut off unit power supply.

2.Loosen fan shaft pulley bushing.

5.Tighten nuts.

6.Adjust bolts and nut on mounting plate to secure motor in ®xed position. Recheck belt tension after 24 hours of operation. Adjust as necessary.

46

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Carrier EK, 48EJ, EW, EY024-048 installation instructions Evaporator Fan Service and Replacement, Typical Gas Heating Section

EW, EY024-048, EK, 48EJ specifications

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