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PBG
II
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L. MAINTENANCE (Continued)
BLOWER MOTOR REPLACEMENT
A. BLOWER MOTOR REMOVAL
1. Power down equipment (burner and blower assembly), disconnect and isolate from
electrical power supply.
2. Verify that the burner and blower assembly is off and can not be restarted and also that
the impeller is not rotating.
3. Open the motor wiring terminal box (A) and remove the electrical power supply wires
from the motor leads. Take note of wiring connection for new motor installation. Refer to
Figure 4 for component identification.
4. Remove the eight sheet metal screws (B) that hold the blower face plate (C) onto the
blower body (I), exposing the impeller (D). Care should be taken not to tear the face
plate gasket (E). If undamaged, the gasket may be reused, set the gasket on a flat
surface and protect from damage.
5. Loosen the two set screws (F) in the impeller hub.
6. Remove the impeller from the motor shaft (penetrating oil or lubricant may be required).
Note that care must be taken not to damage the impeller during this process. Damaging
or bending the impeller will cause an imbalance that will result in excessive vibration
when the impeller is rotating which can damage motor bearings and other coupled
equipment.
7. Secure and support the motor (G) and remove the four bolts (H) that fasten the blower
housing to the motor face. Note removing these bolts will decouple the motor from the
blower housing, the motor must be secured or supported to prevent the motor from
falling and damaging equipment and/or personnel.
WARNING
Local and national codes and standards should be strictly adhered to. Exposure to energy
sources including potential electrical, kinetic rotating mass and combustible fuels will be
encountered during this procedure outlined below. Applicable Lock Out/Tag Procedures
should be followed to prevent fire, explosion, property damage, severe personal injury, or
even death.
All maintenance, repair and wiring to the burner blower, air control motor, and
control accessories must be completed by qualified personnel.
IMPORTANT
If the installation is delayed and the equipment is stored outside,
provide adequate protection as dictated by climate and period of
exposure. Special care should be given to all motors and bearings,
if applicable, to protect them from rain or excessive moisture.
