A Lennox central air conditioner unit can suck up debris through the intake grille and into the condenser fan compartment. Children playing might also insert things into the unit. Either way, debris isn’t good news for a condenser fan. It can wrap around the fan axle or get stuck in the motor, where it can jam the fan and cause the fan motor to burn up. You can look for debris inside the unit by removing the Lennox housing panel.
The Lennox air conditioner fan component ball bearings can grow grimy or become stripped of lubrication over time. This causes the fan to run very slowly or not at all, which hinders cold air production inside the home. The grinding of the bearings could also produce a screeching noise. To eliminate the noise and help the fan to move at its full potential, you can shut off the electricity that flows to the unit at the circuit breaker and remove the Lennox fan-housing panel. Turn the fan manually to test the ball bearing tension. If the fan doesn't turn freely, the ball bearings need to be lubricated. You can insert electric motor oil into the ball bearing ports at the base of the fan axle and turn the fan a few times to work the lubrication into the bearings.
If the entire unit seems like it isn’t getting power, there are two things you can inspect. Locate the power breaker that controls the unit and be sure that the switch is in the “On” position. If it’s in the “Off” or middle position, electricity is unable to flow to the unit. Flip the switch to the “On” position to restore power to the unit and fan. If the circuit breaker is fine, the power lines might be compromised. If you see any frays, tears or dents along the Lennox air conditioner power lines, they should be replaced.
A dirty filter can make the Lennox fan seem like it’s broken. The fan might continue to operate, but air is unable to enter the air conditioner for all the dirt and dust on the air filter. Air filters should be checked often and replaced approximately every four weeks, depending on your air conditioner model. Some filters can be cleaned while others must be replaced. For those that can be cleaned, you can run water on both sides of the filter until all dirt is removed.