How to Replace an AC Compressor

DIY or Call the Pros? Your Guide to AC Compressor Replacement

When your AC stops cooling, a faulty compressor could be to blame. But when it fails, should you tackle the replacement yourself or call in a professional? Replacing an AC compressor isn’t a simple swap—it involves handling refrigerant, electrical components, and precise installation to ensure your system runs efficiently. 

Grove Heating & Cooling walks you through the process, outlining what’s involved, the tools required, and when it’s best to leave the job to the experts.

What Does the AC Compressor Do?

The air conditioner’s compressor is the powerhouse of your cooling system, responsible for circulating refrigerant between the indoor and outdoor units. By pressurizing refrigerant, it’s able to absorb and release heat, which keeps your home cool. 

When the AC compressor fails, your air conditioner can no longer effectively cool the air, leading to issues like weak airflow, warm air blowing from vents, or even a system that won’t turn on at all. Other signs of a failing compressor include loud noises, tripped circuit breakers, and frozen coils. 

Because the compressor is such a critical component, it’s often necessary to replace the AC compressor when it fails—otherwise, your entire cooling system won’t function properly.

Step-by-Step Guide: How to Replace an AC Compressor

Replacing an AC compressor requires specialized tools and technical knowledge to ensure a safe and effective installation—it’s a job best left to HVAC professionals, like the NATE-certified AC repair technicians at Grove Heating & Cooling. 

This step-by-step guide shares what we do when you need an AC compressor replacement, along with the tools needed for each stage.

1. Diagnose the Problem

Before replacing the compressor, we confirm that it is the source of your AC issues. Symptoms of a failing compressor include warm air blowing from vents, loud noises, or a system that won’t turn on. Our HVAC technician uses diagnostic tools like a multimeter and refrigerant gauge set to test the compressor and ensure the issue isn’t related to other components like the capacitor or refrigerant levels.

2. Turn Off Power to the Unit

Safety is critical. We shut off power to the air conditioning system at the circuit breaker to prevent electrical shock. We also turn off the thermostat to make sure the system does not attempt to turn on during the replacement process.

3. Recover the Refrigerant

AC compressors operate with refrigerant, which must be handled properly due to environmental regulations. Our EPA-certified technicians use specialized equipment to safely recover and store the refrigerant before disconnecting the compressor.

Tools Needed:

• Refrigerant Recovery Machine: To safely remove refrigerant from the system.
• Recovery Cylinder: To store the recovered refrigerant for proper disposal or reuse.
• Manifold Gauge Set: To monitor refrigerant pressure during the recovery process.

This step is critical, as improper handling of refrigerant can result in legal penalties and environmental harm.

4. Disconnect the Old Compressor

Once the refrigerant has been removed, the faulty compressor is disconnected. This step includes:

• Removing the electrical connections.
• Disconnecting the refrigerant lines.
• Unbolting the compressor from its mounting bracket.

Tools Needed:

• Wrench Set: To loosen and remove the mounting bolts.
• Adjustable Pliers: To handle small connections and fasteners.
• Tubing Cutter: If necessary to cut and prepare refrigerant lines for reconnection.
• Socket Set: For removing compressor bolts.

Care must be taken to avoid damaging other system components during the removal of the old AC compressor.

5. Install the New Compressor

The replacement compressor is carefully positioned and secured. This step includes:

• Connecting the refrigerant lines.
• Reattaching the electrical wiring.
• Securing the unit to its mounting bracket.

Tools Needed:

• Torque Wrench: To properly tighten bolts to manufacturer specifications.
• Refrigerant Line Flaring Tool: If flaring is needed for connections.
• Pipe Bender: If refrigerant lines need adjusting for proper fit.

Proper alignment ensures the AC compressor replacement functions correctly and does not cause system vibrations or leaks.

6. Recharge the Refrigerant

With the new AC compressor in place, refrigerant must be added to the system. This requires precise measurement and proper handling techniques for safety and efficiency.

Tools Needed:

• Manifold Gauge Set: To measure refrigerant pressure levels.
• Vacuum Pump: To remove any air or moisture from the system before recharging.
• Refrigerant Scale: To measure and add the exact amount of refrigerant needed.

7. Test the System

Once the system is reassembled, turn the power back on and test the AC compressor. This includes:

• Checking for refrigerant leaks.
• Ensuring proper electrical connections.
• Monitoring the compressor’s operation and cooling performance.

Tools Needed:

• Leak Detector: To check for refrigerant leaks.
• Infrared Thermometer: To measure temperature changes and ensure proper cooling.
• Clamp Meter: To verify electrical current levels in the compressor.

DIY or Hire a Professional to Replace Your AC Compressor?

Replacing an AC compressor is a technical and labor-intensive process requiring specialized tools and HVAC knowledge. Handling refrigerant, electrical connections, and system calibration isn’t just difficult—it also requires certifications in many areas. 

If you suspect your AC compressor needs replacement, Grove Heating & Cooling is here to help with expert air conditioning repair service and reliable solutions. Contact us today to diagnose your AC issues and perform the repairs or component replacement services you need to stay cool.