10 AC Unit Parts Critical For Maintaining Comfort

When it comes to staying cool in the scorching Texas heat, your air conditioning unit is your best friend. But like any hardworking machine, it relies on several key components to function efficiently. Understanding these essential AC parts can help homeowners recognize issues early and prevent the need for air conditioner repairs. 

In this guide, we outline the most critical parts of an air conditioning system, their functions, common issues, troubleshooting tips, and average replacement costs for each component.

Some of The Most Critical AC Unit Parts & Their Function:

1. AC Compressor

Function: The AC compressor is often referred to as the heart of the AC system. Compressors pressurize and circulate refrigerant, enabling heat exchange and cooling.

Common Issues & Troubleshooting:

• Overheating: Dirty coils or low refrigerant can cause overheating. Cleaning the coils and checking refrigerant levels may resolve the issue.
• Hard Starting: If the AC struggles to turn on, a faulty capacitor or electrical issue could be the culprit.
• Loud Noises: Rattling or clanking may indicate internal damage, such as loose AC unit parts or failing bearings.

Average AC Compressor Replacement Cost: $1,200 – $2,500 (varies by unit size and brand)

2. Air Conditioner Evaporator Coil

Function: The AC evaporator coil absorbs heat from the indoor air, allowing the refrigerant to cool and dehumidify the air before it is circulated back into your home.

Common Issues & Troubleshooting:

• Frozen Coils: Restricted airflow due to dirty filters or low refrigerant can cause freezing. Turn off the unit and let it thaw, then check for airflow obstructions.
• Corrosion & Leaks: Over time, evaporator coils can corrode and develop refrigerant leaks. If you notice poor cooling, a professional should inspect for AC leaks.

Average AC Evaporator Coil Replacement Cost: $600 – $2,000

3. AC Condenser Coil

Function: Located in the outdoor unit, the AC condenser coil releases the heat absorbed from inside your home, allowing the refrigerant to cool down and repeat the cycle.

Common Issues & Troubleshooting:

• Dirty Coils: A buildup of dirt and debris can reduce efficiency. Regularly clean the condenser with a garden hose and coil cleaner.
• Refrigerant Leaks: If the system isn’t cooling effectively, low refrigerant levels due to leaks may be the issue. Professional servicing is required.

Average AC Condenser Coil Replacement Cost: $900 – $2,800

4. Expansion Valve (TXV)

Function: The expansion valve regulates the flow of refrigerant into the evaporator coil, ensuring proper cooling.

Common Issues & Troubleshooting:

• Clogged or Stuck Valve: If the valve becomes clogged, the system may not cool efficiently. A professional technician can diagnose and replace it if necessary.
• Incorrect Superheat Readings: If the valve is not adjusting properly, it can cause inconsistent cooling. A professional should recalibrate or replace the valve.

Average Expansion Valve Replacement Cost: $300 – $600

5. AC Blower Motor

Function: The AC blower motor powers the fan that pushes cooled air through your home’s ductwork.

Common Issues & Troubleshooting:

• Weak Airflow: Clogged filters or a failing motor can lead to poor airflow. Replacing the air filter may help, but a worn-out motor requires replacement.
• Strange Noises: Grinding or squealing sounds may indicate a failing motor bearing or belt that needs servicing.

Average AC Blower Motor Replacement Cost: $400 – $1,500

6. Air Conditioning Capacitor

Function: AC Capacitors provide the necessary electrical charge to start and keep the compressor and fan motors running.

Common Issues & Troubleshooting:

• AC Won’t Start: A failed capacitor can prevent the AC from turning on. A professional can safely replace it.
• Clicking Sounds: A capacitor that struggles to hold a charge may cause clicking noises when the AC tries to start.

Average Air Conditioning Capacitor Replacement Cost: $150 – $400

7. AC Contactor

Function: Air Conditioner contactors are an electrical relay that controls power to the compressor and condenser fan.

Common Issues & Troubleshooting:

• AC Won’t Turn On: A faulty contactor may prevent the system from starting. Replacement is usually necessary.
• Pitting & Corrosion: Wear and tear over time can cause electrical arcing, leading to failure.

Average AC Ontactor Replacement Cost: $100 – $350

8. Air Conditioning Thermostat

Function: Your air conditioner’s thermostat controls your AC system, allowing you to set and maintain desired temperatures.

Common Issues & Troubleshooting:

• Incorrect Temperature Readings: If the thermostat isn’t calibrated correctly, it may cause inconsistent cooling. Replacing the batteries or recalibrating can help.
• Unresponsive Controls: If the thermostat is unresponsive, checking the wiring or upgrading to a smart thermostat may be needed.

Average AC Thermostat Replacement Cost: $100 – $500 (basic to smart thermostats)

9. AC Air Filters

Function: AC Filters remove dust, allergens, and debris from the air, improving indoor air quality and system efficiency.

Common Issues & Troubleshooting:

• Restricted Airflow: Dirty filters can strain the blower motor, reducing efficiency. Filters should be replaced every 1-3 months.
• Increased Energy Bills: A clogged filter forces the AC to work harder, increasing energy costs.

Average HVAC Air Filter Replacement Cost: $10 – $50 per filter

10. AC Refrigerant

Function: AC refrigerant is the fluid that absorbs and releases heat, allowing the cooling cycle to occur.

Common Issues & Troubleshooting:

• Leaks: Low AC refrigerant levels can cause poor cooling performance. Only a certified HVAC technician can safely recharge the system.
• Environmental Concerns: Older AC units may use refrigerants like R-22, which are being phased out due to environmental concerns. Upgrading to an energy-efficient model may be necessary.

Average AC Refridgerant Recharge Cost: $200 – $600 (varies by refrigerant type and amount needed)

Cruz Air & Electric: We Keep All of Your AC Unit Parts Running Smoothly 

There are main critical and even complex AC unit parts, all working together to maintain your comfort. Understanding these components can help you identify early signs of trouble and prevent costly breakdowns. If you’re experiencing AC issues or need professional AC maintenance, Cruz Air & Electric is here to help! 

Contact us today at 281-46-4272 for expert AC repairs, replacements, and AC tune-up services to keep your home cool all year long!