a guide to the condensor fan motor and replacement

The Condensor Fan Motor Guide

The AC condenser fan motor plays a major part in the successful operation of your HVAC system. Without proper maintenance it may wear, resulting in a poor air flow and unstable heating and cooling conditions. These motors are designed with balanced rotors to help reduce noise and vibrations during use.

What is a condensor fan motor?

The cool air in a conditioner is created by the condenser unit and the motor drives the fan which blows the air through the condensor coils, converting hot refrigerant gas into cool liquid.

The condenser fan motor blows the cool air round the house, keeping you cool in the summer and a well-maintained fan motor can prolong your AC unit.

How do I know if my condensor fan motor is bad?

Overheating can be an issue with air condition+ing units and when your unit is hot to touch, you know there is an issue that needs addressing. Any problems with the condenser fan motor can lead to your AC unit overheating, and this is probably the best place to start looking. With regular cleaning and maintenance, the condenser fan motor should run smoothly. You should always consult a qualified contractor to maintain and check your fan motor, as they usually need specific oils to keep working.

What happens when a condenser fan motor fails?

When the motor fails, your AC unit will become hot and emit a slight odor. It will stop pushing out cold air and could damage your air conditioning unit. When this happens, it is best to shut it down and call an engineer.

What causes a condenser fan motor to fail?

There are many reasons it may fail, with the most common being, a lack of lubricant, a failed bearing in the belt drive, water in the windings, voltage problems or a failed run capacitor.

Why is my AC fan making a noise?

If a fan becomes loose or needs cleaning it will start to hum or rattle. Open up your air conditioning unit, locate the fan motor and check to make sure it is clean with no debris around the blades. Occasionally, bits of dirt or insulation may become loose and fall onto the blades. So, keeping it clean will help to keep it working properly.

Other ways to fix a noisy fan include:

  • Tightening the blade screws
  • Examine the blades to make sure they are not bent or unbalanced
  • Secure the fan motor canopy
  • Lubricate the condenser fan motor
  • Clean the blades and vents

How to replace a condensor motor fan

Switch off the power supply and turn the blades round. If they do not spin smoothly and are not obstructed or bent, then it is likely to be the motor that needs replacing.

Here are 7 factors to be noted before buying a new fan motor;

  • The mounting – they are not all the same
  • Shaft size
  • RPM speed
  • Rotation direction of shaft
  • Motor measurements
  • Horsepower rating
  • Voltage

Before removing anything, you must make sure all power is disconnected and unplugged. The make a note of all the existing wiring conditions. Take a photograph to remind yourself of what colors go where.

Unscrew all bolts that hold the motor in place and remove the fan blade, making a note of how it attaches to the shaft.

Now replace with the new motor and re-attach the fan blade in the same way you took it off.

It is always advisable to replace the air conditioning unit’s run capacitor, following all the advice above, copying wiring, color coding and installation. Unscrew it from the unit and replace the capacitor with a new one that matches the technical information of the old one. Sometimes they will come in different shapes and sizes, but if you have the right technical details, you cannot go wrong.

Once you have replaced the capacitor and condenser fan motor, clean everywhere, making sure there is no dust or debris in the AC unit. Power back up and test everything is working correctly.

Checkout our selection of condensor motors here.