How To Troubleshoot 4 Common Furnace Problems

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Your furnace is one of the most important appliances in your home, and it is important to address furnace problems as soon as they appear so that you are not left in the cold. Unfortunately, furnace repairs are often somewhat expensive, with an average cost of $394 nationwide. Before you call a technician to repair your furnace, use a these simple troubleshooting steps for common problems so that you may avoid a furnace repair bill.

Furnace is Not Producing Heat

If your furnace is not producing heat, it is possible that the problem originates with the thermostat. The first step you should take is to check that the temperature of the thermostat is above the current room temperature. This will assure that the thermostat is sending a call to the furnace to begin heating. Many thermostats also have a switch that must be set to "heat" instead of "cool" to activate the furnace.

If the thermostat is set correctly, you should check that the breaker that controls your furnace has not been tripped. The problem could also originate with a blown fuse. Troubleshooting the electrical components that provide power to your furnace can resolve your heating problem without requiring you to perform any repairs on the furnace itself.

Blower Motor Will Not Turn Off

The air handling system beneath your furnace contains a blower motor that blows air past the heat exchanger and into your duct system. If the blower motor is not shutting off when it is supposed to, you will hear your furnace constantly running and will continue to feel air coming out of your vents. 

To troubleshoot this problem, first make sure that the switch on your thermostat is set to "auto" instead of "on." This should prevent the blower from running constantly and instead cause it to shut off when the temperature in your home has matched the thermostat setting. If this does not solve the problem, you should inspect your air filter. If your air filter is clogged, it is possible that it has damaged the limit switch inside of your furnace. The limit switch is responsible for deactivating the blower motor before the temperature inside your furnace reaches dangerous levels. You should clean the filter and replace the limit switch to resolve this problem.

Furnace Makes Unusual Noises While Running

There are a few different problem that can cause excessive noise while your furnace is operating, and specific problems can often be identified by the type of noise that you hear. A high-pitched squealing sound is a common result of a worn or slipping blower belt. You can easily replace the belt yourself  by purchasing a replacement belt based on the manufacturer's specifications.

You may also hear a rumbling or vibrating noise while your furnace is running. A common cause of this problem is a loose panel that needs to be pressed firmly into place to suppress the vibration. If none of the panels are loose, a rumbling sound could indicate that the blower wheel is imbalanced or dirty, and you should call a professional technician to correct this problem.

Furnace is Starting and Stopping Too Frequently

If your furnace is starting and stopping too frequently, it will fail to heat your home properly. The most common cause of this problem is that your furnace is overheating during operation and is shutting off automatically as a fire safety mechanism.

Fortunately, this behavior of starting and stopping indicates that the limit switch is still doing its job properly and does not need to be replaced. You will likely be able to solve the overheating problem by cleaning or replacing your clogged furnace filter. When your unit is fitted with a clean filter, the filter will no longer block the much-needed air flow that cools the inside of your furnace.

By taking a few simple steps to troubleshoot your furnace problems, you can often save yourself the time and cost of calling a professional technician or click here for furnace repair.