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9 Most Common Reasons for Furnace Failure

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Homeowners in the Janesville, WI, area count on their furnaces to stay warm through the winter months. Unfortunately, sometimes your heating system may stop working. Understanding the most common reason for furnace failure helps you identify and address any problems with the system.

Find out more about possible problems with your furnace and set up an appointment for repairs with Rock Valley HVAC, Inc. Reach us at (608) 496-9993 to get started.

#1: Insufficient Maintenance

Many furnace issues develop due to a lack of proper maintenance. In fact, inadequate service may represent the most common reason for furnace failure.

Most furnaces require yearly maintenance to continue operating at peak efficiency. The experts generally recommend a service appointment in the fall, before winter hits, if you have an electric, propane, oil, or gas furnace.

During the maintenance appointment, furnace experts check all moving parts and tune up the system. Crews clean all components of the furnace, including the following:

●      Blower motor

●      Forced vent motor

●      Flame sensor 

Maintenance appointments allow technicians to identify any problems before they lead to a breakdown. You may decide to replace parts of the furnace as they wear out instead of allowing them to fail completely. 

Service appointments also help your furnace run more efficiently, which may reduce your energy expenses through the winter months. 

#2: Normal Wear and Tear

Over time, the parts in your furnace wear out due to regular usage. Sometimes, this wear and tear causes a furnace failure. We see several common problems caused by the effects of time, including:

●      Problems with airflow

●      Issues with heat control

●      Overheating

If you experience any of these issues with your furnace, reach out to a heating system professional to assess the underlying cause of the problem.

#3: Clogged Filters

Your furnace moves air through your home or business. This air passes through a filter as it travels through the ductwork, with the filter catching contaminants like pet hair, dander, pollen, and dust. Over time, filters fill up and become clogged if you don’t change them regularly.

Clogged filters restrict airflow through your heating system. Your furnace must work much harder to force air through a dirty filter, generating unnecessary strain on the system, increasing your energy bills, and adding more wear-and-tear on the furnace.

Sometimes, filter clogs lead to limit switch damage, which may cause your furnace to stop working. Consider addressing this issue yourself by regularly replacing the filter in your system. Make sure that you select a filter that fits the heater for the best results. 

#4: Issues with the Thermostat

When considering the most common reason for furnace failure, we recommend focusing on thermostat issues. Your thermostat allows you to control the temperature setting for your furnace. If the thermostat stops responding, you cannot easily turn your furnace on or off.

Fortunately, thermostat issues do not typically cause damage to the furnace, but they can prevent you from sending signals to your heating system. In some cases, the thermostat refuses to work because it has dead batteries.

Change and replace the batteries in the thermostat to troubleshoot this problem. If your thermostat remains inoperative, reach out to a furnace repair specialist for assistance. 

#5: Faulty Ignition Switches or Pilot Controls

Some furnaces use an electric ignition while other systems have a pilot light. Issues with these systems prevent your furnace from turning on. Your pilot light must remain lit for a gas furnace to operate. The following issues sometimes cause a pilot light to go out:

●      Clogs in the furnace system

●      Drafts

●      Thermocouple malfunctions

A furnace repair team can address any of these issues, getting your furnace up and running again. 

#6: Issues with an Improperly Sized Furnace

HVAC teams need to properly size your furnace before installing the heating system. A heater too small for your property may end up failing as it struggles to heat the complete square footage of your home. 

Furnace systems that are too large also generate problems over time. These furnaces end up turning off too quickly, leaving your property with uncomfortable cold spots. They also create higher humidity levels in your home in some situations.

#7: Clogs in the Condensation Pipe

Many furnaces produce moisture as a result of the air cooling around your combustion fuel. These systems use condensation pipes to take moisture away from the furnace and to a drain. However, clogs sometimes develop in the condensation lines. 

You may notice leaking around your furnace in this situation. Allowing a clog to go unaddressed for an extended period may cause additional problems for your furnace, eventually leading to a failure in some circumstances. 

Learn why your AC is leaking and discuss solutions to the problem with a team of heating system experts. 

#8: Air Flow Issues

Your furnace heats your home by drawing cooler air over a series of heating elements. Diminished airflow – due to clogs or issues with a blower fan – negatively impacts the functionality of your heating system.

You may notice airflow issues before they cause a furnace failure if you pay attention to the operation of your heater. Furnaces often begin cycling on and off frequently when they experience airflow restrictions, preventing the furnace from completely heating your home. 

Reduced airflow also causes some furnaces to start making odd noises. Consider contacting a professional for assistance if your furnace begins:

●      Rattling

●      Squeaking

●      Rumbling

Getting help right away helps reduce the odds of a complete furnace failure. 

#9: Limit Switch Failure

The limit switch controls several components in your furnace, most notably the blower. If your limit switch wears out, it may cause the blower to run continuously. Constant operation leads to increased strain for your furnace and may contribute to a failure in some situations. 

Professional furnace repair crews know how to replace a limit switch, restoring your furnace to proper operating condition.

most common reason for furnace failure

How to Handle a Furnace Failure

If your furnace fails for any of the above reasons, you can move quickly to address the issue. Going without a working furnace in the winter leads to discomfort and may even cause problems with the water pipes in your house if the temperatures get far below freezing.

Handle a broken furnace by:

Scheduling Repairs

Furnace repair technicians move quickly to get your heating system up and running again in Edgerton and the surrounding areas. Crews arrive at your property quickly and assess your situation. Technicians may replace parts to get your furnace operational once more. 

Replacing Your Furnace

You may replace your furnace after a major breakdown. Speak with a professional to determine if it’s more cost-effective to repair the system or install a new heater.

Most heating systems last around 15 to 20 years. If you have an older system that breaks down repeatedly, it may be time to consider investing in a new furnace. You have multiple options to control the temperature in your home, including:

●      Furnaces

●      Boilers

●      Heat pumps

Some property owners decide to switch from a furnace to a heat pump after a breakdown. Heat pumps take care of warming your house in the winter and also provide air conditioning services. 

Go Over Reasons for a Furnace Breakdown

The most common reason for furnace failure often comes down to a lack of maintenance or age. Our team at Rock Valley HVAC, Inc. can step in to help property owners after they experience an issue with their heating system. Reach out to our HVAC contractors in Edgerton by calling (608) 496-9993.