Before installing a new blower motor, the old one has to be removed. Start by turning off the power to the furnace, writing down the wire colors and where they are connected. The bolts should be removed, and then the blower assembly can be slid out of the system.
The motor is still in the assembly, so the screws on the assembly need to be loosened; then the mounting bolts should be removed. Once the old motor is removed, the new motor can be put in by reversing the removal procedure. One of the things that a person should remember to properly install the motor is to make sure the wheel is centered in the housing before the wheel is secured to the motor.
It is also important to ensure that the proper rotation direction for the motor has been selected. If there are unused motor leads, they should be isolated individually by using electrical tape or wire nuts. It is also a good idea to replace the run capacitor when the motor is replaced. When the installation is finished, it is also important that normal furnace blower operation is checked. The installer should listen for any noises, and make sure that air is coming out of all supply registers.