Why Furnace Tripping Your Circuit Breaker?

A furnace is an essential appliance that plays a critical role in maintaining comfortable indoor temperatures, especially during the winter months. However, like any electrical appliance, a furnace can malfunction and cause significant problems. One of the most common issues that homeowners face is when the furnace keeps tripping breaker, which can result in a loss of heat, potential damage to the furnace, and a safety hazard. 
In this comprehensive guide, we will know what is a circuit breaker, various reasons why a furnace may trip the circuit breaker and offer possible solutions to rectify the issue. Whether you are a homeowner, landlord, or tenant, let us find out the underlying causes of furnace tripping breaker and how to fix them.

What is a circuit breaker? How does a circuit breaker work?

A circuit breaker is an electrical device that automatically cuts off power supply to a circuit when there's an electrical fault. It is designed to protect electrical appliances and prevent electrical fires caused by overload or short circuiting. The circuit breaker is usually installed in a circuit panel box and can be reset once the problem has been fixed.

How does a circuit breaker work?

Electrical faults increase current flow, heating wires and possibly starting fires. The circuit breaker monitors the current flow and detects any abnormal surge in electricity. The circuit breaker trips if the current is too high. The furnace circuit breaker, for instance, is specifically designed to protect the heating system from electrical damage.

Once the electric furnace circuit breaker has tripped, the switch moves to the off position, disconnecting the power from the circuit. This protects the electrical system and your home. Flip the switch back on to reset the circuit breaker. However, it's important to first identify and fix the root cause of the problem to prevent the furnace keeps tripping breaker in the future. If you're in need of top-quality furnace circuit breaker and other HVAC parts, look no further than PartsHnC. We offer a vast selection of products from the industry's leading manufacturers, ensuring that you'll find exactly what you need to keep your HVAC systems running smoothly. 

Now that you know what is a circuit breaker and how does a circuit breaker work. Let us find out what causes a furnace to trip the circuit breaker.

What would cause a furnace to trip a Circuit breaker?

A furnace can trip a circuit breaker for various reasons. One common cause is an overload in the electrical system. This can happen if the furnace motor or blower draws too much power. Another possibility is a short circuit, which occurs when a wire or component within the furnace malfunctions and creates a sudden surge of electrical current. Additionally, a faulty circuit breaker or wiring in the home's electrical system can cause repeated tripping of the breaker. If the problem persists, it's important to have a professional electrician or HVAC technician diagnose and repair the issue to ensure safe and efficient furnace operation.

Know about the Installation steps and Cost of a circuit breaker. 

Why Does a Furnace Trip Your Circuit Breaker?

There are several potential reasons why your furnace may be tripping the circuit breaker. Most commonly, the issue arises from an overload of electrical current or a short circuit. Below are some of the leading causes for a furnace to trip the breaker:

Overloaded Circuit

The most frequent cause of a furnace tripping the circuit breaker is an overloaded circuit. Each furnace is powered by a dedicated circuit that can handle a specific electrical load. If the circuit is overloaded, the breaker will trip to prevent damage. An overload occurs when too much power is drawn through the circuit, causing it to exceed its rated capacity.

In some cases, this overload can occur if you have other high-power appliances plugged into the same circuit. Furnaces use a significant amount of electricity, and combining them with other power-hungry devices (such as a microwave, space heaters, or a refrigerator) can easily lead to an overload.

Short Circuit

A short circuit occurs when an unintended path allows electricity to flow directly from the power source to the ground. This causes an excessive amount of current to flow, tripping the breaker. In furnaces, a short circuit can occur due to damaged wires, worn-out insulation, or faulty electrical components within the unit.

Short circuits can be dangerous as they often generate significant heat and can cause a fire if not dealt with promptly. They can occur in various furnace components, such as the fan motor, the control board, or the thermostat wiring.

Faulty Furnace Components

A malfunctioning furnace component could also cause the circuit breaker to trip. This could include issues like a faulty blower motor, a malfunctioning thermostat, or a failing capacitor. Each of these components can draw too much current when they are not operating properly, leading to an overload situation.

For example, if the blower motor is seized or running with excessive friction, it will require more electricity to run, which could cause the circuit breaker to trip. Similarly, a malfunctioning thermostat could send signals that cause the furnace to run in an erratic manner, consuming more power than necessary.

Electrical Connection Issues

Another cause of breaker trips could be poor electrical connections. Over time, electrical connections within your furnace can become loose or corroded. A poor connection can cause an increase in resistance, which, in turn, leads to breaker overheating and higher energy consumption. This overheating will trigger the circuit breaker to trip.

Issues like damaged wiring or faulty connections can also cause arcing. Arcing occurs when electricity jumps across a gap in the wiring, creating sparks and heat, which can overload the circuit.

Dirty Furnace Filters

While a dirty furnace filter may not directly trip the circuit breaker, it can contribute to overheating and other issues that might. A clogged filter restricts airflow, causing the furnace to overheat as it tries to force air through the system. The increased strain on the system can cause the furnace to draw more power, potentially tripping the breaker.

In some cases, the overheating can cause the furnace's internal components to fail, such as the fan motor or heat exchanger, leading to a short circuit or overload.

Incorrect Breaker Size

Each furnace requires a circuit breaker of a specific size to handle the power demands of the system. If the breaker is too small for the furnace, it may trip frequently due to the normal operating load. On the other hand, an oversized breaker can fail to trip during an overload situation, leading to potential hazards.

For example, if your furnace is rated for a 30-amp breaker and you install a 20-amp breaker, the smaller breaker may trip more easily, even during normal use. Conversely, installing a 50-amp breaker for a smaller furnace may not trip during an overload, increasing the risk of electrical damage or even fire.

Overworked Furnace

Sometimes, a furnace can trip a breaker simply because it is overworked. This could happen during extreme weather, especially in extremely cold climates where the furnace is running continuously for extended periods. If the furnace is working harder than usual, the increased power draw can overwhelm the electrical system, tripping the circuit breaker.

Additionally, older furnaces or units that have not been maintained properly may require more power to run efficiently. If your furnace is frequently tripping the breaker during heavy use, it may be time for a tune-up or replacement.

Grounding Issues

Grounding issues can also cause a furnace to trip its circuit breaker. Electrical systems rely on proper grounding to direct excess electrical current safely into the ground. If the furnace is improperly grounded, the circuit may become overloaded, resulting in a tripped breaker.

Grounding problems can also be the result of faulty wiring, outdated systems, or damage caused by wear and tear over time. If your furnace is tripping the breaker frequently, grounding issues may be at play.

Here is a Guide to choose the best furnace. 

How to Troubleshoot Furnace Tripping a Circuit Breaker?

Here’s the step-by-step guide on how to prevent furnace tripping breaker:

Step 1: Turn off the furnace: Before beginning any troubleshooting, turn off the furnace to ensure your safety. You can do this by flipping the switch on the furnace itself or the circuit breaker panel.

Step 2: Check the circuit breaker: If the circuit breaker trips, check it. If so, turn it on and see if it trips again. Proceed if so.

Step 3: Check for overloading: Furnaces require a lot of energy to operate, and if there are too many other appliances drawing power from the same circuit, it can cause the circuit breaker to trip. Check if any other devices or appliances are running on the same circuit as the furnace, and if so, unplug them and try turning the furnace back on.

Step 4: Check the air filter: The furnace can overheat and trip the circuit breaker if the air filter is dirty. If the air filter is dirty or clogged, replace it.

Step 5: Check the blower motor: Furnace air is circulated by the blower motor. If it malfunctions, the furnace may overheat and trip the circuit breaker. Stop the furnace and call a pro if you hear any.

Step 6: Check the thermostat: A faulty thermostat can cause the furnace to run continuously and overheat, which can trip the circuit breaker. Check the thermostat by turning off the furnace and removing the cover to access the wiring. 

Step 7: Check the electrical components: If all else fails, there may be an issue with the electrical components within the furnace. This can be dangerous to reset a tripped circuit breaker the technician should only handle.

Safety Precautions to Take : When troubleshooting a furnace tripping breaker, it's important to take safety precautions to prevent injury or damage to your home. Before starting any work, turn off the furnace and unplug it from the power source.

When to Call a Professional

If you've tried all the troubleshooting steps and your furnace is still tripping the circuit breaker, it's time to call a professional. There may be an underlying issue with the electrical system or the furnace itself that requires the expertise of a trained technician. Attempting to fix the problem on your own can be dangerous and may cause further damage to your furnace or home.

Know more about How to replace your Furnace blower motor. 

Tips for Preventing Furnace Circuit Breaker Tripping

Furnace circuit breakers can be dangerous. Luckily, there are several ways to avoid this issue. Here are some tips for preventing furnace circuit breaker tripping:

Regular Furnace Maintenance

Regular furnace maintenance is crucial for preventing circuit breaker tripping. A professional should inspect and service your furnace once a year. A technician can clean the furnace, check for any issues, and make any necessary repairs before they turn into larger problems. A clean and properly functioning furnace will run more efficiently and reduce the chances of tripping the circuit breaker.

Proper Use of Thermostat

Another factor that can lead to circuit breaker tripping is improper use of the thermostat. Make sure you're not setting the temperature too high, which can cause the furnace to work harder and draw more power. Also, avoid constantly adjusting the temperature, as this can cause the furnace to turn on and off frequently, which can overload the circuit breaker. Set your thermostat at a comfortable temperature and leave it alone.

Upgrading Electrical Panel or Circuit Breaker

If your furnace is tripping the circuit breaker frequently, it may be time to upgrade your electrical panel or circuit breaker. Older homes may not have the capacity to handle the electrical load of a modern furnace. In this case, upgrading your electrical panel or circuit breaker can help prevent tripping and improve the safety of your home's electrical system.

By understanding the common causes of furnace tripping breaker and taking the necessary steps to address them, you can ensure that your furnace operates safely and reliably. From checking the air filter to scheduling professional maintenance, there are a variety of steps you can take to prevent furnace tripping and keep your home warm and comfortable.

FAQ’s 

How Do You Reset a Furnace Circuit Breaker?

Here’s how to reset furnace circuit breaker: 

• First turn off the thermostat and then locate the circuit breaker panel for your furnace. 

• Once you've found the right breaker, flip it to the "off" position and wait for about 30 seconds. 

• Then, switch the breaker back to the "on" position. 

• Finally, turn on your furnace at the thermostat and check if it's functioning properly. 

• If the breaker trips again, it's important to contact a qualified technician to inspect your furnace and identify any underlying issues.

How Much Does a 20 Amp Circuit Breaker Cost?

The cost of a 20 Amp circuit breaker can vary depending on the brand, type, and seller. On average, a basic 20 Amp circuit breaker can cost anywhere from $5 to $20, while more advanced or specialized models can cost up to $100 or more. It's important to note that installation costs are not included in the price of the circuit breaker.

How to replace a circuit breaker?

Here is how to replace a circuit breaker in your furnace:

• Turn off the power to the circuit by switching off the main circuit breaker.

• Remove the cover panel of the circuit breaker box to access the circuit breaker.

• Remove the wire from the faulty breaker by gently pulling it out of the terminal.

• Remove the faulty breaker by pulling it out of the slot and set it aside.

• Install the new breaker by lining it up with the slot and pushing it in until it snaps into place.

• Reconnect the wire to the new breaker by inserting it into the terminal and tightening the screw.

• Replace the cover panel and turn the power back on to the circuit.

How to find what is tripping my circuit breaker?

To find out what is tripping your circuit breaker that controls your furnace, you should follow these steps”

• Turn off all appliances and devices that are connected to the same circuit as the furnace.

• Reset the circuit breaker and turn on the furnace.

• If the circuit breaker trips again, it means the problem is with the furnace itself. Contact a qualified HVAC technician to diagnose and fix the issue.

• If the circuit breaker does not trip, turn on each device or appliance one at a time to see if any of them cause the breaker to trip. If one of them does, it may be faulty and needs to be repaired or replaced.

At what temperature does a circuit breaker trip?

The temperature at which a circuit breaker trips for a furnace depends on the specific model and rating of the breaker. Generally, circuit breakers for furnaces are designed to trip at a temperature range of 170-250 degrees Fahrenheit (76-121 degrees Celsius) to protect against overheating and potential fire hazards. However, it is important to refer to the manufacturer's specifications for the specific breaker to determine the exact temperature at which it will trip.