Are you ready to learn more about your furnace circulation
blower fan motor and how to replace it? Our blog post will tell you everything
you need to know and talk you through the process of replacement.
What is the Furnace
Circulation Blower Fan Motor?
As part of the heating or cooling system, the furnaces
circulation blower fan motor draws air through the return vent, blows it past
heat exchanger, and forces it through the homes venting. The room air is
then drawn back with the return and the air flow cycle continues. The blower
fan motor can run at multiple speeds to improve efficiency. Lower speeds are utilized
when the furnace is heating, and speeds are used for air conditioning.
A malfunctioning blower fan motor is going to be unable to provide
heated or cooled air throughout the home. If the blower fan motor is noisy
during use, the set screw on the blower wheel may have loosened, resulting in the
wheel to wobble on the motor shaft. You can fix this problem by tightening or
replacing the screw, or replacing the blower wheel all together.
If the motor itself is noisy, the bearings within the motor may
have worn out. Although some older furnace motors can be lubricated to reduce the
noise, most up to date motors do not allow this and the motor will need to be
replaced.
If the blower motor does not run at all, you should first
confirm that the motor is receiving power. If it's, then it's likely the motor
has burned out.
Circulation blower fan motors are often unique to each
furnace model. You need to enter the full model number of your furnace in our
website search bar to obtain the specific fan motor you need.
How to Replace Your Furnace
Circulation Blower Fan Motor
Before you replace the fan motor, first switch off the power
to the furnace.
The blower fan motor is normally supported on rails close to the
bottom of the furnace. Because the motor power wires are connected to a control
board that is often located in an upper compartment, two access panels may need
to be removed. If applicable, you need to ensure the motors run capacitor is
discharged by putting a screwdriver with an insulated handle across the
terminals. Avoid touching the screwdriver blade. Disconnect the wires in the capacitor
terminals, if required. Depending on the furnace model, you may have to
uninstall a drain trap assembly, and the attached hoses to access the fan motor.
If required, you may need to disconnect the thermostat wires in the control
board to move them out of the way. Note the orientation from the blower motor
power wires, then disconnect them from the control board. Cut any zip ties if
required. Move any additional obstructions out of the way. If necessary, note
in which the blower assembly mounting rails are positioned. Now unthread the
screws securing the rails. Carefully slide the blower assembly. Use an
adjustable wrench to loosen the set screw to release the blower wheel from the
motor shaft. If required detach the grounding wire. Cut any zip ties securing
the motor wires. Now unthread the bolts or screws securing the blower motor. Note
the orientation from the old motor, then lift it off of the blower housing.
When installing a brand new blower motor, you should make sure
the motors capacitor rating matches the present run capacitor. If not, you
will need to replace the capacitor with the required one. Insert the fan motor
shaft in to the blower wheel, as you properly align the motor on the housing. Thread
and tighten the bolts or screws to secure the motor. Use zip ties to secure the
wires and reattach the grounding wire if required. With the flat side of the
motor shaft facing the set screw, center the blower wheel within the housing and
tighten the set screw. Realign the blower assembly mounting rails with the
slots on the support, and slide the assembly in place. Replace the screws
to secure the rails. Reinstall any components you removed earlier. Attach the
blower motor power wires to the appropriate terminals on the control board.
Connect the capacitor wires, as required. If applicable, reconnect the
thermostat wires as well. Use zip ties to remove any slack from the wiring.
With the new blower motor installed, replace the access
panel or panels. Turn the ability supply back on, and your furnace should be
ready for use.
Watch our video on replacing your furnace circulation blower fan motor for any visual guide, or visit Repair Clinic for additional furnace repair tips.
