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A Guide to Professional AC Motor Replacement

If you are like most homeowners, you probably give little thought to the parts that keep your AC running until something goes wrong. Whether you’re dealing with weak airflow, no airflow, or an AC that isn’t turning on at all, the problem could be caused by an issue with an AC motor. In fact, your air conditioner has several motors that must all be working to ensure proper functioning.

Although some motor issues are easier to fix than others, finding the source of the problem and getting it repaired requires extensive HVAC knowledge and training and is not a task for a DIYer. At Landry Mechanical Inc Plumbing HVAC & Electric in Sutton, MA we are available to repair and replace AC motors. The following covers the different types of AC motors, what motor replacement and repair entail, and why you should always leave the task up to the pros.

Condenser Motor

Regardless of which motor appears to be the offender, a professional will always follow a specific diagnostic process to determine the problem. Performing an electrical diagnosis can help a technician find the cause of the issue and decide whether a repair or replacement is necessary. For suspected condenser motor issues, we will electrically test both the capacitors and the motor.

Your condenser motor sits outside year-round, so it is exposed to the elements and can get very hot. Often, a capacitor that has overheated and failed is the cause of condenser motor issues. If the condenser motor and capacitor need to be replaced, our technician will take note of several things, including the motor’s:

  • RPM
  • Mount
  • Voltage and horsepower
  • Shaft size
  • Motor diameter
  • Proper fan rotation direction

It’s important that the replacement motor matches these specifications or the AC will not function properly and other issues could occur. To replace the motor, the technician will first shut down all electricity to the AC for safety. Then, they can remove wiring, supporting bolts and screws, and fan blades, taking note of the placement of all components so that they can be properly connected to the replacement motor. Once the motor is removed, its replacement can be installed by simply reversing the removal process. After installing the new motor, the technician will restore power and check to ensure that the AC is operating correctly.

Blower Motor

The blower motor is another crucial AC component that must be operating correctly for the AC unit to function. During the diagnostics phase, the technician will check for issues that commonly lead to blower motor failures. One of the main causes is overheating due to clogged motor vent holes. A capacitor failure can also cause the fan to turn backward and eventually fail.

Regardless of the issue, the motor replacement process is largely the same and typically involves capacitor replacement as well. As with all replacement jobs, the first step is to shut off power to the AC. Then, the technician will discharge the capacitor and sketch a diagram or take a picture of wiring connections and placement before disconnecting the motor wires. To remove the motor, the technician will remove the nuts connecting the blower motor to the fan guard grille and then loosen the set screw securing the fan blade to the condenser motor. At this point, the blower motor can be removed and replaced by reversing the steps above. Once in place, the system will be tested for proper operation.

ECM Motor

ECM motors run blowers in higher-end air conditioning units with variable-speed motors. Because they are located in the same place as a traditional blower motor, physical replacement typically involves the same steps listed in the previous section. However, ECM motors have a computer that controls the fan speed, and the computer requires proper programming. At times, HVAC companies must send out to a supply house to have a new ECM motor programmed, but some can be programmed by a smartphone with a corresponding app. Due to the technical aspects of proper ECM programming and the cost of these motors, specialized training is needed to work on them, so more experience HVAC techs typically perform these replacements.

Compressor Motor

The compressor motor, which is actually two motors in one, is the most difficult of all the AC motors to diagnose and replace. First, it’s in a sealed housing, so it isn’t possible to simply determine visually if it is operating. There are three terminals sticking out of the motor that the technician will check using a voltmeter to ensure that each one is within the proper range and sending a charge to the ground. If there isn’t any power, it could mean that the motor has failed. However, compressor motors have an internal safety switch that cuts off power to the motor if it overheats, so it’s important that the technician checks to see if the switch has been activated before moving on with a replacement.

Replacement involves removing the refrigerant from the system, cutting refrigerant lines, disconnecting electrical connectors, and unbolting the motor from the unit. Because the process is somewhat complicated and compressor motors are quite expensive, the technician may recommend having the entire AC unit replaced instead of just the compressor motor, especially if the AC is 10 years old or older.

Why Leave AC Motor Replacement to the Professionals

While you may be tempted to watch a few YouTube videos and read some guides online and then replace an AC motor yourself, this is never a good idea. First of all, DIY replacements put your safety at risk. In addition to significant amounts of electricity, AC units use refrigerants that can cause severe respiratory issues if inhaled. Saving a few bucks is not worth risking injury or even death.

Without the proper knowledge and training, it’s also highly likely that you will cause more damage. This means that you’ll end up having to pay for professional repairs anyway, and they’ll likely be much more expensive than they would have been if you had called a pro in the first place. Reaching out to a professional for motor replacement also ensures that your system gets the proper diagnosis and that the root cause of the issue is addressed. Often, a professional will find other minor issues that can be fixed before they turn into costly repairs.

Air Conditioning Repair in Worchester County and the MetroWest Area

At Landry Mechanical Inc Plumbing HVAC & Electric in Sutton, we are your local experts for air conditioning repair in Worchester County and the MetroWest area. We provide heating and air conditioning installation, repair, and maintenance. We also provide a full range of heating, plumbing, and electrical services. We have been serving our local community since 2008, and we’re proud to have a reputation for exceeding our customers’ expectations. The Better Business Bureau has accredited us and given us their highest rating due to our top-notch services. We offer installation financing on approved credit, and we also work with you to help you get rebates, especially ones offered here in Massachusetts.

Call Landry Mechanical Inc Plumbing HVAC & Electric in Sutton for all of your air conditioning repair needs.

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