Can Your Air Conditioner Cause a Power Surge? Here's What You Need to Know

Your air conditioner’s outdoor unit is built to handle fluctuations in power—but it’s not immune to power surges. In fact, a surge can happen without warning and cause serious damage before you even realize there’s a problem. Depending on the severity, your system could require anything from a simple repair to a full replacement. Curious whether your A/C could trigger a power surge—or how to stop one before it starts? In this post, we’ll explain how issues like faulty wiring or overworked components can lead to surges, and how preventative steps like surge protection and regular maintenance can help reduce the risk.

Can Your Air Conditioner Cause a Power Surge?

To understand how your air conditioner can cause a power surge, you should learn how the equipment operates. When the thermostat triggers the system to turn on, you’ll notice a significant draw in amperage between the compressor and the fan motors. The capacitor provides this jolt of electricity and keeps the energy running smoothly during operation. As the A/C makes its way through the cycle, it will decrease in energy consumption and eventually stop. Once the thermostat triggers the system again, the entire cycle starts over.

Although it’s not commonplace, the system can fail. Power surges can come from a variety of places, often from elsewhere in your electrical system or the power grid. Surges from the A/C equipment itself are possible, and they can cause a lot of damage. If the circuit cannot handle the amperage draw or if you have faulty wiring, you could end up with an unexpected surge. It’s wise to try to anticipate your risk of a power surge because the damage surges cause can lead to expensive repairs or early replacement of your A/C.

What Actually Causes a Power Surge in the First Place?

Many things can cause a power surge, and you need to know where it is coming from so you can take action. A power surge is defined as a spike in voltage that exceeds normal function, depending on the voltage of the outlet, typically over 120 volts. Most air conditioning units and heat pumps use 240-volt currents, while a ductless mini-split or regular home outlet usually uses 120 volts.

When an electrical surge happens, you may observe the circuit breaker tripping, which shuts off the power to devices on that circuit. It is not the same as a blackout. Blackouts are a complete loss of power, usually through some interruption to the power grid. Brownouts refer to a lower flow of voltage that causes lights to dim and electronic devices to reduce or change function.

You might always notice a power surge. Air conditioners are designed to handle some malfunction before they totally break down, even if they are taking damage in the process. Likely, you will first observe changes to function, like a sudden shutoff or insufficient cooling.

Even one power surge can cause damage to the system. The control board, capacitor and sensors could sustain damage that leads to improper operation or system failure. A modern A/C unit requires regular access to electronic controls, which makes it even more sensitive to electrical problems. As such, you should target prevention and protection as your main methods for reducing risk.

Common A/C Problems That Lead to Surging

When you think about the operation of your air conditioner, you may be surprised by the number of things that can interrupt its function or efficacy. With the right unfortunate combination of problems, many of these issues can lead to a power surge. The most common issues requiring a cooling services for HVAC emergency response include:

Faulty Compressor Operation: If your compressor is old or oversized or if it is overworking due to another condition, it can trigger a power surge in its attempt at normal operation.
Dirty Air Filters or Coils: Dirt or debris on your coils, or clogged filters, force the system to work harder. This situation can put stress on other components, increasing the likelihood of a surge.
Low Refrigerant Levels: Insufficient refrigerant requires the system to cycle constantly, which can increase power demands and cooling load. Stressed components are more likely to fail, leading to surges or other air conditioner overload problems.
Failing Capacitors and Contactors: Capacitors and contactors control the flow and amount of energy to the system. Faulty components may cause energy levels to spike, leading to a surge.
Wiring Issues: Loose or damaged connections at the A/C system or electrical panel, or faults in the wiring, can trigger a surge.

Understanding how these issues can affect your A/C system is key to determining how to address electrical issues caused by A/C.

Can a Power Surge Damage Your A/C Unit?

Power surges can damage almost any electronic equipment in your home, which includes your air conditioner. Here are a few signs of damage that you may notice:

Control Board: The control board may eventually stop working due to repeated surges even if you don’t spot a change in operation initially.
Thermostat: If the thermostat fails to turn on, even if you replace the batteries, you may have damage from a power surge.
Compressor: A failing compressor may short cycle or provide insufficient cooling, leading you to schedule A/C repair to discover the cause.
Blower Motor: A faulty blower motor may quit working entirely or show a decrease in airflow throughout the home.
Fuses: Blown fuses, resulting from excess amperage, often cause the A/C system to stop working directly. If you notice a blown fuse, you should presume that the system has sustained a power surge.

Power surges may trigger damage to other household systems depending on the source. A surge of voltage through the power grid could fry the wiring, trigger a shutdown of the circuit or destroy appliances. To avoid having to deal with these issues or replace expensive components, you should consider your options for protection.

How to Prevent A/C-Related Power Surges

If you want to work on protecting A/C from power surges, you should take the following steps:

Whole-Home Surge Protection: Installing a whole-home surge protector for A/C can control the flow of energy directly from your circuit panel, diverting excess voltage to the ground.
Individual HVAC Surge Protection: If you can’t get a whole-home surge protector, consider surge protection for HVAC equipment. These devices install directly to the condenser or air handler to offer additional protection.
A/C Maintenance: A well-kept air conditioning system or heat pump reduces stress on the system. Keep your coils, fins and fans clean and in good condition for optimal output that minimizes damage.
Professional Inspections: Hiring an HVAC technician to inspect your system annually can help to ensure that your equipment is in ideal condition, as well as giving you advance notice about wear or damage that may cause a power surge.

Although some of these approaches can be costly, prevention is often much less expensive than replacing your A/C system.

Do You Need a Whole-Home Surge Protector for Your HVAC System?

Before you schedule electrical services for surge protection solutions, you should understand the benefits and considerations involved in whole-home surge protection. Buying a whole-home surge protector is an investment, but it can protect various systems in your home. When you plug a surge protector into an outlet inside your home, it can help to minimize excess voltage running to the device. Individual surge protectors don’t prevent damage, however, to other devices or systems.

By comparison, a whole-home surge protector installs directly to your electrical panel, controlling the flow of energy to every device. It can help to prevent damage from lightning strikes, utility switching or internal cycling. Unprotected, these events may lead to damage to sensitive electrical components like control boards or the compressor. Although installing a surge protector is not a replacement for regular upkeep and inspections, it can help to save money on fried components and give you peace of mind during the next storm.

When to Call a Professional

If you suspect that your A/C is causing a power surge, you should pay attention to these signs that you need A/C repair:

Circuit Breaker Tripping: A sudden power loss from A/C often leads to a tripped breaker. Call a professional if it keeps tripping.
System Won’t Turn On: If you can’t get your A/C to operate at all, calling a professional is key to getting it working again.
Signs of Power Surges: If you have other signs of power surges, such as loss of power or other fried electronics, you may need an HVAC inspection to determine the extent of the power surge damage.

Annual maintenance plans, such as MendelCare, can provide professional protection against damage. Power surges seem rare, but they can cause more damage than you might think. We can help you determine if a whole-home surge protector is right for your home and keep your A/C system in top working order. To learn more about our services, contact us today!