Commonly Malfunctioning Components in AC Systems
  • Posted on May 16, 2023
  • By Rod Miller

Have you ever found yourself baffled by the inner workings of household appliances? The intricate technical information surrounding these machines may appear mundane or even superfluous at first glance. However, delving into this knowledge can be a game-changer, making your life remarkably more convenient. And yes, your AC system is no exception.

Your air conditioning system is an intricate combination of indoor and outdoor units that work harmoniously to keep your home cool and comfortable. However, just like any mechanical system, it is susceptible to problems and malfunctions. 

So, let’s dive in and explore the top five components of your AC system that commonly malfunction. By the end of this article, you’ll have a solid understanding of these issues and be empowered to take the necessary steps to keep your system running smoothly.

Note: We know this information may seem a bit technical. However, homeowners should have a basic understanding of the components that can malfunction in their AC systems. 

1. Faulty Controls

One of the most common problems homeowners encounter with their AC systems is faulty controls. These issues can range from a malfunctioning thermostat to a broken circuit board. The control board is a critical component responsible for regulating the system’s operations, such as temperature control and activating the blower. When these controls malfunction, they can disrupt the overall efficiency of your HVAC system, resulting in discomfort and potential energy waste.

If you suspect an issue with your thermostat or control board, it’s crucial to address it promptly. Reach out to our team of skilled technicians who can diagnose the problem and provide expert solutions. Remember, even seemingly minor control issues can significantly impact your system’s performance.

Here’s a few signs that your control board may be malfunctioning.

1. Blinking Lights: Check for LED lights on the access panels of your HVAC system – if they’re blinking, it could indicate a potential issue.

2. Inconsistent Temperature: Fluctuating or extreme temperature changes in your home might point to a malfunctioning control board.

3. Stuck Switches: Control board switches can become sluggish or stuck over time, similar to other devices that aren’t used frequently.

If you’re experiencing any difficulties with your AC controls or suspect a malfunction, reach out to our team for professional assistance. We’ll ensure that your system operates optimally, providing you with comfort and peace of mind.

2. External Safety Switch Issues

Your AC system is equipped with external safety switches designed to protect it from potential damage. These switches are triggered when the system fails to perform within specified parameters. 

They are meant to shut down your AC unit to prevent further issues. However, these safety switches are sometimes triggered unnecessarily, causing an unnecessary shutdown.

Various factors can cause safety switch activation, such as low or high refrigerant pressure or a malfunctioning condensate pump. 

If you notice your AC system frequently shutting down, it’s essential to have a qualified technician investigate the cause. Our experienced team can identify the underlying problem and provide the necessary repairs or replacements to restore your system’s functionality.

If you’re experiencing frequent system shutdowns or suspect an issue with your external safety switches, don’t hesitate to contact us.

3. Compressor Problems

The compressor is the heart of your air conditioning system. It plays a crucial role in the refrigeration process, compressing the refrigerant and facilitating the cooling cycle. Without a properly functioning compressor, your AC system won’t be able to provide the desired cooling effect.

Understanding the cooling process can shed light on the importance of the compressor. The refrigeration cycle begins with the refrigerant absorbing heat from a room, causing it to change from a cold liquid to a low-pressure, warm refrigerant gas in the evaporator coil. The compressor then compresses the gas, converting it into a high-pressure, hot gas. 

Heat is removed as the gas enters the condenser, transforming it into a high-pressure, cool liquid. The expansion valve lowers the pressure and temperature, turning it back into a cold gas and restarting the cycle.

When the compressor experiences problems, it can hinder the entire cooling process. Compressor motor failure, refrigerant leaks, or electrical faults can lead to inadequate cooling or even complete system breakdown. If you suspect compressor issues, it is crucial to seek professional assistance to diagnose and resolve the problem effectively.

If you notice any signs of compressor problems, such as inadequate cooling or unusual noises, contact our expert technicians immediately. We have the expertise to diagnose and address compressor issues, ensuring your AC system operates at its best.

4. Faulty Coils

Your air conditioning system relies on two types of coils: condenser coils and evaporator coils. Each coil serves a vital function and contributes to the efficient operation of your AC system. However, problems with these coils can disrupt the cooling process and lead to system breakdown.

The evaporator coil inside your home absorbs heat from the indoor air and releases it outside. Just before entering the evaporator coil, the refrigerant passes through an expansion chamber, rapidly cooling it before it flows through the cooling coils. These cooled coils absorb heat from the air passing over them, thus cooling the air sent back into your home.

On the other hand, the condenser coil, located in the outdoor unit, releases the heat absorbed from indoors into the atmosphere. After absorbing heat from the indoor air, the refrigerant passes through a compressor, rapidly increasing its pressure, causing it to become blisteringly hot. As the refrigerant moves through the condenser coil, a large fan pulls air across it to remove as much heat as possible.

Issues with either the evaporator or condenser coils can be detrimental to your AC system’s performance. Coil problems may arise from dirt and debris buildup, corrosion, or refrigerant leaks. Unfortunately, coils typically need to be replaced rather than repaired.

If you suspect any issues with your evaporator or condenser coils, having them inspected and serviced by our qualified technicians is crucial. Reach out to us for professional assistance in resolving coil-related problems and ensuring optimal cooling performance.

5. Metering Device Malfunction

The metering device is a vital component in an air conditioning system that plays a crucial role in regulating refrigerant flow. Its primary function is to decrease the temperature and pressure of the refrigerant as it moves from the condenser to the evaporator. There are different types of metering devices used in HVAC systems, each with its specific charging method, all of which are essential for the system’s proper operation.

The metering device is engineered to control the refrigerant flow into the evaporator, ensuring that the pressure is regulated effectively. It facilitates a high side-to-low side pressure and temperature drop necessary for the cooling process to occur efficiently.

However, metering devices can experience malfunctions over time, leading to problems within the air conditioning system. Common issues with metering devices include clogs or restrictions in the refrigerant lines, faulty expansion valves, or improper refrigerant charge. These malfunctions can disrupt the proper flow of refrigerant, resulting in reduced cooling capacity.

If you suspect a malfunctioning metering device in your air conditioning system or experience issues with cooling capacity or temperature control, reach out to our experienced HVAC technicians. We will assess the situation and provide the necessary repairs or replacements to ensure your system operates at its best.

Ready to Keep Your AC System Running Smoothly?

Understanding the most common problems with residential air conditioning units can empower homeowners to take proactive steps in maintaining their HVAC systems. From faulty controls and external safety switch issues to compressor problems and faulty coils, each of these issues can disrupt the functionality of your AC and impact your comfort.

If you encounter any of these problems, it is crucial to seek professional assistance from skilled HVAC technicians. At Rod Miller, we pride ourselves on providing reliable and efficient HVAC repair services to ensure the comfort of your home.

Our highly skilled and knowledgeable technicians are dedicated to addressing your HVAC needs promptly and effectively. Whether you’re facing issues with your AC, or any other HVAC system, we have the expertise to diagnose and repair the problem efficiently. Reach out today here or call 301-569-7993 for assistance!


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