When your AC stops working, it's like the sun decides to make your home its vacation spot—uninvited and overwhelmingly warm. Have you ever asked, "Why did my AC stop working?" You're not alone. This sudden switch from cool to warm air can turn any day into a sweltering puzzle, leaving you scrambling for AC repair services to find solutions.

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In this article, we dive deep into the heart of the problem:

  • Uncover common reasons behind why your AC stopped working, from simple fixes to complex issues.
  • DIY troubleshooting tips that could save you time and money before calling in the pros.
  • Preventative maintenance practices to keep your AC running smoothly, avoiding future breakdowns.

Understanding Your AC's Operation

Knowing how your AC system functions can demystify the process when something goes wrong, like when your AC stops working. At its core, an AC unit is quite a team player, with each component playing a crucial role in cooling your home.

Basic AC Functionality

An AC system works by moving heat from inside your home to the outside, thus cooling the interior. This process involves several key components:

  • Compressor: Think of the compressor as the heart of your AC system. It circulates refrigerant between the indoor and outdoor units, changing it from gas to liquid. This cycle is essential for the AC to cool your home.
  • Evaporator: The evaporator coil is like a sponge. It absorbs heat from the air inside your home. As warm air passes over these coils, the refrigerant absorbs the heat, cooling the air blown back into your room.
  • Condenser: On the flip side, the condenser coil releases the absorbed heat outside. It's located in the outdoor unit and is critical in expelling unwanted heat from your home.
  • Expansion valve: This part controls refrigerant flow to the evaporator. It adjusts the amount of refrigerant based on how much cooling is needed, making it the system's regulator.
  • Air filter: While not directly involved in the refrigeration cycle, the air filter is vital for maintaining air quality and protecting the system from dust and debris. A clean air filter ensures efficient operation and is key to preventing your AC from stopping working.

Types of AC Systems

Understanding the different AC systems can help you better diagnose issues when your AC stops working. Each system has its unique setup and common troubleshooting areas.

Central AC units are the most comprehensive option, designed to cool the entire house through a network of ducts. They're efficient for large spaces but can face issues like duct leakage or uneven cooling.

Window units are perfect for cooling single rooms. They're compact and easier to install but may need help with drainage issues or might not cool as efficiently if not properly sealed in the window.

Split systems offer a balance between the two, with an indoor and outdoor unit but without the need for extensive ductwork. They're great for targeting specific areas but can cause problems with the refrigerant levels or electrical connections.

Here's a quick guide to help differentiate them further:


Type Pros Cons Common Issues
Central AC Efficient for whole-house cooling Requires ductwork; higher installation cost Duct leakage; thermostat problems
Window Unit Easy to install; cost-effective Cools only single rooms; can be noisy Drainage issues; poor insulation
Split System No ductwork is needed; quiet operation Higher cost than window units Refrigerant leaks; electrical issues


When troubleshooting, consider the system type. For example, inspect the ducts for leaks if your central AC is not cooling evenly. Check for gaps around the installation if your window unit isn't cooling efficiently. For split systems, ensure the indoor and outdoor units communicate properly and have adequate refrigerant levels.

Initial Checks for a Non-Working AC

When your AC stops working, it's easy to think the worst. However, a few simple checks can often reveal easy fixes. Before calling in the professionals, let's go through some basic troubleshooting steps.

Verify the Power Supply

Your AC's power supply is where troubleshooting should start. A lack of power could be the reason your unit isn't working. Here's what to check:

  • Main Electrical Panel: Look for tripped breakers. If you find any, flip them off and then back on. Sometimes, this is all it takes to get your AC running again.
  • External Disconnect Switch: Most outdoor units have a switch nearby. Ensure it's in the "on" position. This switch can sometimes be turned off accidentally.
  • Check for Blown Fuses: If your unit still doesn't start, the issue might be a blown fuse in the disconnect box next to the outdoor unit.

These steps help ensure that the problem isn't just a simple power supply issue, saving you time and possibly money.

Thermostat Troubleshooting

The thermostat is your AC's command center. If it's not set correctly, your AC won't know to start cooling. Make sure you:

  • Set it to Cooling Mode: It sounds simple, but ensure your thermostat is set to cool, not just the fan or heat.
  • Lower the Temperature: Setting the temperature lower than the current room temperature can kickstart your AC.
  • Check the Batteries: Some thermostats need batteries. If yours is battery-powered, try replacing them to see if that solves the issue.

Common Issues and DIY Fixes

When your AC stops working, it's not always a sign of a major system failure. Sometimes, the culprit is as simple as a dirty air filter, which can greatly affect your system's efficiency and airflow.

Dirty Air Filter Consequences

A clogged air filter is a common issue that can lead to various problems with your AC system. How it impacts your unit:

  • Reduced Airflow: When the filter is clogged with dust, pet dander, and other debris, air cannot flow freely through your system. This reduced airflow can cause the unit to work harder, leading to inefficiency and increased energy costs.
  • Poor Cooling Performance: With obstructed airflow, your AC cannot cool your home as effectively. You might notice that some rooms feel warmer even when the AC is running.
  • Increased Wear on AC Components: Over time, the extra strain on your AC due to a dirty filter can lead to wear and tear on its parts, potentially shortening the lifespan of your unit.

To tackle this issue, here's what you can do:

  • Regularly Check and Replace Your Air Filter: Make it a habit to check your air filter every month, especially during high-use seasons like summer and winter. If the filter looks dirty, it's time for a change. Typically, replacing your air filter every 90 days is a good rule of thumb, but this can vary based on your specific situation, such as having pets or allergies.
  • Choose the Right Filter: Not all air filters are created equal. Make sure to select one that fits your system's requirements. Some filters are designed to capture more particles, which is beneficial for maintaining indoor air quality but may need to be changed more frequently.
  • DIY Cleaning for Reusable Filters: If your system uses a reusable filter, you can clean it according to the manufacturer's instructions. Usually, this involves rinsing it with water and letting it dry completely before reinserting it into your unit.

Condensate Drain Line Clogs

To address condensate drain line clogs, it's essential to understand their common causes and impacts. A clogged drain line can lead to water leaks and high humidity inside your home, affecting comfort and potentially causing water damage. Here's a simplified approach to handling this issue:

  • Locating the Drain Line: Typically found near the outdoor unit, the drain line is a PVC pipe directing condensation away from your AC system.
  • Inspection Tips: Look for signs of leakage or overflow near the drain line exit. Clear any visible debris around the area.
  • Clearing Clogs: Use a wet/dry vacuum to suction any blockages from the drain line's end. Alternatively, a gentle flush with water and vinegar can help clear minor clogs and prevent algae or mold growth.

Regular maintenance, including periodic checks and cleaning of the condensate line, can prevent clogs and ensure your system runs efficiently.

Inspecting the Outdoor Unit

The outdoor unit plays a crucial role in your AC's ability to cool your home efficiently. Keeping it clear of obstructions and regularly cleaning it can improve performance and extend the unit's lifespan.

  • Removing Obstructions: Ensure a 2-foot clearance around the outdoor unit. Remove any leaves, twigs, or debris that could block airflow.
  • Cleaning Tips: Gently hose down the unit to remove dirt and debris from the fins. Avoid using high pressure, which can damage the fins.
  • Professional Inspection: While basic cleaning can be done DIY, consider a professional service for a thorough inspection and maintenance, including checking coolant levels and electrical connections.

ac stopped working Plano TX

Advanced Troubleshooting Techniques

When your AC stops working and simple fixes aren't cutting it; it might be time to delve into more advanced troubleshooting techniques. One critical area to check is the refrigerant levels in your system.

Checking Refrigerant Levels

Refrigerant is the lifeblood of your AC system, circulating through coils to cool and dehumidify your home. However, if your system runs low on refrigerant, it's a sign of deeper issues, such as leaks, requiring professional intervention.

Here's how to spot the warning signs:

  • Warm Air Blowing from Vents: If the air from your vents isn't as cold as it should be, low refrigerant levels could be the culprit.
  • Ice Buildup on Outdoor Unit: Seeing ice on your compressor or refrigerant lines indicates that something's not right with the refrigerant flow.
  • Hissing or Bubbling Noises: Sounds of hissing or bubbling can point to refrigerant escaping through leaks in your system.

The implications of ignoring these signs can be severe, affecting your comfort and causing potential damage to the compressor, leading to costly repairs or even system replacement. Here's what to do if you suspect refrigerant issues:

  • Contact a Professional: Refrigerant levels, pressure checks, and leak repairs on your ac are tasks for certified technicians. Handling refrigerants requires specialized tools and knowledge, as well as adherence to environmental regulations.
  • Regular Maintenance: Schedule regular maintenance checks to prevent future refrigerant issues. Technicians can spot early signs of wear and tear, ensuring your system remains sealed and operates efficiently.

Evaluating Electrical Components

When an AC stops working, inspecting the electrical components becomes crucial. This includes a careful look at contactors, capacitors, and other electrical parts that play a pivotal role in the operation of your AC system. Here's how to approach this safely and effectively:

  • Contactors act like switches controlling the power supply to different AC unit parts. Signs of wear include pitting or corrosion on the contact points. If the contractor doesn't engage, your system won't receive power where it needs it, leading to malfunction.
  • Capacitors: They help start the motor and keep it running by storing and releasing electrical energy. A failing capacitor may result in your AC system struggling to start or shutting off unexpectedly. Bulging or leaking fluid from capacitors are clear indicators they need replacement.
  • Safety First: Always ensure your AC system is powered off before inspecting these components. This includes turning off the breaker and the external safety switch near your unit. A multimeter can be used to confirm there's no residual power.
  • Visual Inspection: Look for any visible signs of damage or wear on these components. This includes burnt wires, corrosion, or any physical damage to the parts.
  • Testing: Using a multimeter, you can test the continuity and resistance of these components. However, calling a professional is safer and more efficient if you're unfamiliar with handling electrical tests.

When to Call a Professional

Dealing with AC stopped-working issues can be tricky, especially regarding refrigerant problems. These issues are not just complex; they're also potentially hazardous if not handled correctly. It's crucial to know when to step back and call a professional.

Recognizing Refrigerant Issues:

Refrigerant issues are a common culprit behind AC inefficiencies and failures. Some symptoms indicate a refrigerant problem, signaling it's time to call in the experts:

  • Hissing Noises: This sound can indicate a refrigerant leak. Refrigerant escaping from tiny holes in the coils produces a distinct hissing sound.
  • Ice on the Evaporator Coils: If you notice ice buildup on the coils inside your unit, it could mean the refrigerant levels are too low, causing the coils to freeze.
  • Warm Air Blowing: When the AC is set to cool but is blowing warm air, it could be due to inadequate refrigerant levels.
  • Short Cycling: If your AC unit turns on and off more frequently than normal, it could struggle to maintain the desired temperature due to a refrigerant issue.
  • Increased Energy Bills: An unexplained spike in your energy bills could result from your AC working harder to cool your home, possibly due to a refrigerant problem.

Electrical and Mechanical Failures

When your AC stops working, the root cause might not always be straightforward. Sometimes, the issue lies deep within the system's electrical or mechanical components. These scenarios often require a keen eye and professional expertise for accurate diagnostics and repair.

  • Repeated Breaker Trips: If you find yourself constantly resetting the circuit breaker for your AC unit, it's a sign of an electrical issue that demands professional attention. This could indicate an overload, a short circuit, or a problem with the AC unit.
  • Unfamiliar Noises: Any new or strange sounds from your AC unit, such as buzzing, rattling, or screeching, could point to mechanical failures. Each sound can indicate a problem, from loose parts to a failing compressor.
  • AC Unit Fails to Start: If your AC unit doesn't respond to thermostat commands and fails to start, it could be due to an electrical failure, such as issues with the control board, thermostat wiring, or capacitor problems.
  • Frequent Cycling or Shutting Off: Should your AC unit turn on and off more frequently than normal or suddenly shut off, it might be struggling with its electrical connections or experiencing a mechanical fault that prevents it from running correctly.

ac stopped working Plano

Preventive Maintenance Tips

Maintaining your AC system is not just about fixing issues as they arise; it's also about preventing those problems from occurring in the first place. Let's explore some essential preventive maintenance tips that can keep your system running smoothly and efficiently.

Regular Cleaning and Servicing

Keeping your AC system clean and service is crucial for its efficiency and longevity. Here are some key points to remember:

  • Annual Inspections: Have a professional thoroughly inspect your AC system at least once a year. This can help catch potential issues before they lead to a system breakdown.
  • Clean or Replace Air Filters: Dirty air filters can restrict airflow, reducing efficiency and potentially causing damage. Check filters monthly and replace or clean them as needed.
  • Keep the Outdoor Unit Clear: Ensure the area around your outdoor unit is free from debris, leaves, and other obstructions. This helps maintain proper airflow and system efficiency.

Regular cleaning and servicing can significantly impact your AC's performance, helping to avoid unexpected breakdowns and costly repairs.

Investing in a Maintenance Plan

A maintenance plan with a trusted HVAC service provider is an investment in the health of your AC system. Here's why it's worth considering:

  • Priority Service: Many plans offer priority scheduling for their members, ensuring you get the service you need quickly, even during peak seasons.
  • Cost Savings: Routine maintenance can identify and fix minor issues before they become major problems, potentially saving you money on repairs and energy bills.
  • Extended Lifespan: Regular maintenance helps ensure your AC system runs efficiently for as long as possible, extending its lifespan and maximizing your investment.

Enhancing Your AC's Performance and Lifespan

Keeping your AC system in top condition ensures comfort during hot weather and extends the unit's lifespan. One innovative way to enhance performance and efficiency is upgrading your thermostat technology.

Upgrading Thermostat Technology

Switching to a smart thermostat can significantly impact your AC's efficiency and operational capabilities. Here's how:

  • Improved Efficiency: Smart thermostats learn your schedule and preferences, adjusting your AC's operation accordingly. This means your AC only works when needed, saving energy and reducing wear on the system.
  • Remote Control: A smart thermostat can control your AC from anywhere using a smartphone app. If you forget to adjust the thermostat before leaving home, you can do it remotely, ensuring you don't cool an empty house.
  • Maintenance Reminders: Many smart thermostats offer maintenance reminders, alerting you when it's time to change your air filter or schedule a service visit. This helps keep your system running smoothly and prevents minor issues from turning into major problems.
  • Energy Usage Reports: Get detailed reports on your energy usage and tips on reducing it. This can help you make informed decisions about your AC's operation, potentially saving you money on your energy bills.

Energy Efficiency Improvements

Enhancing your home's energy efficiency is a smart way to improve your AC's performance and reduce energy costs. Here are several effective tips for insulating and sealing your home, ensuring cool air stays in and hot air stays out:

  • Seal Windows and Doors: Check for drafts around windows and doors. Use weather stripping or caulk to seal any leaks, keeping the cool air inside where it belongs.
  • Upgrade Insulation: Proper insulation in your attic, walls, and floors minimizes heat transfer from outside. This means your AC doesn't have to work as hard to maintain a comfortable temperature.
  • Use Window Treatments: Thermal curtains or blackout blinds can significantly reduce heat gain from windows. Close them during the hottest day to keep your rooms cooler.
  • Install Door Sweeps: Placing sweeps on the bottom of exterior doors can help prevent warm air from entering and cool air from escaping.
  • Consider Window Films: Solar control window films can reflect a significant portion of incoming heat, helping to keep indoor spaces cooler and reduce the burden on your AC system.

Navigating AC Replacement or Repair Decisions:

Deciding whether to repair or replace your AC unit can be challenging. It involves weighing several factors to determine the most cost-effective and efficient path forward. Let's explore some key considerations that can guide your decision-making process.

When to Consider AC Replacement

Several signs indicate it might be time to replace your AC unit rather than repair it. Here are some crucial factors to consider:

  • Age of Your Unit: If your AC is over 10-15, it might be time to consider a replacement. Older units are less efficient and more prone to breakdowns.
  • Escalating Repair Costs: When the cost of repairs approaches 50% of the value of your system, it's generally more economical to replace it. Frequent repairs can also add up, making replacement a more sensible option.
  • Efficiency Ratings: Modern AC units are significantly more energy-efficient than older models. Upgrading to a new system can reduce your energy bills and improve the comfort of your home.
  • Frequent Breakdowns: If your AC unit requires constant repairs to keep it running, it's a sign that it's reaching the end of its lifespan. Replacing it can save you the hassle and expense of ongoing maintenance issues.
  • Inconsistent Temperatures: Struggling to maintain consistent temperatures throughout your home can indicate that your AC unit can no longer effectively cool your space.

Choosing the Right AC for Your Home

Selecting a new AC system for your home is a critical decision that affects your comfort, energy consumption, and utility bills. To make an informed choice, consider the following guidelines:

  • Sizing: The size of the AC unit is crucial. A system that is too large will cycle on and off too frequently, reducing its efficiency and lifespan. Conversely, a unit that's too small will struggle to cool your home, leading to excessive wear and tear. To find the right size, a professional HVAC technician should perform a detailed load calculation considering your home's size, layout, insulation, and other factors affecting cooling needs.
  • SEER Ratings: The Seasonal Energy Efficiency Ratio (SEER) rating measures how efficiently an air conditioner operates over a typical cooling season. A higher SEER rating means greater efficiency and lower energy costs. While units with higher SEER ratings can be more expensive upfront, they often offer significant savings in the long run through reduced energy bills.
  • Features for Improved Comfort and Energy Savings: Modern AC units have various features that enhance comfort and efficiency. Look for units with programmable thermostats, variable speed motors, and features like Wi-Fi connectivity for easy control from your smartphone. These features allow for more precise temperature management, improved air quality, and the convenience of adjusting settings remotely.
  • Energy Star Certification: Choosing an AC unit with Energy Star certification ensures you get a product that meets strict energy efficiency guidelines set by the U.S. Environmental Protection Agency. Energy Star-certified air conditioners use significantly less energy than standard models, which can save you money and help protect the environment.
  • Warranty and After-Sales Support: The warranty and support offered by the manufacturer are also important. Look for units with comprehensive warranty coverage, including parts and labor for several years. Additionally, consider the manufacturer's reputation for customer service and support if you encounter any issues with your new AC system.

ac stopped working in Plano


Navigating AC troubles can be daunting, but maintaining an efficient and effective system is straightforward with the right approach and professional support. From initial troubleshooting to recognizing when it's time for professional intervention, professionals offer the expertise that residents trust.

Frequently Asked Questions

What can cause my AC to stop working suddenly?

Several factors can cause your AC to stop working abruptly, including a tripped circuit breaker, a malfunctioning thermostat, a clogged air filter, a faulty compressor, or a refrigerant leak. It's crucial to have a professional diagnose the issue to prevent further damage (Smart AC Solutions; Jacobs Heating).

How often should I replace or clean my AC filters?

AC filters should be checked monthly and replaced or cleaned as needed. For homes with constant AC use or pets, filters may need to be changed more frequently. Many experts recommend changing filters every 30 to 90 days to maintain optimal air quality and efficiency (HowStuffWorks).

Can a power surge cause my AC to stop working?

Yes, a power surge can trip the circuit breaker or damage the AC's electrical components, preventing it from working. After a surge, check your electrical panel and reset any tripped breakers. If the AC still doesn't work, professional help may be needed to assess and repair any damage (Smart AC Fix).

Why is my AC running but not cooling the house?

Common reasons include a dirty air filter, low refrigerant levels, a frozen evaporator, or a dirty condenser coil. These issues can restrict airflow or reduce the AC's cooling capacity. Adjusting the thermostat, cleaning the filters, and ensuring no blockages can help, but refrigerant issues require professional attention (HowStuffWorks; Jacobs Heating).

How can I tell if my AC needs more refrigerant?

Signs of low refrigerant include reduced cooling performance, hissing noises, or ice buildup on the refrigerant lines. Low levels often indicate a leak, which needs professional repair. After fixing any leaks, a technician can recharge the system with the correct amount of refrigerant (HowStuffWorks).

Ready for Reliable AC Services in Plano, TX?

In the heart of Plano, TX, GO Heating, Air & Plumbing is your go-to expert for all AC repair and maintenance needs. Our commitment to fast, effective, and reliable solutions ensures your comfort is never compromised. By leaning on the expertise of GO Heating, Air & Plumbing, you're choosing a partner committed to your comfort and satisfaction, ensuring your AC system performs at its best when you need it the most.