What Are The Top Problems A Furnace Could Experience?

Homeowners might find a home with a relatively new furnace to be a plus. A newer furnace could perform with excellent efficiency and reduced heating bill costs. Many companies produce top-quality models known for exceptional performance, but all heaters could suffer from maintenance issues.

Some problems are impossible to ignore, and subtle troubles may be worse than a homeowner realizes. Not fixing a defect could lead to things breaking down or malfunctioning at the worse possible time. Delaying repairs may drive the costs upward, which could be frustrating when fixing things earlier might have been less expensive.

Homeowners are not HVAC technicians, so they may not know when something’s wrong. Recognizing the top signs of furnace problems could allow a homeowner to get a qualified technician to handle things.


A furnace’s filter serves an essential purpose. The filter captures dirt and other debris, keeping the fan from circulating impurities through the ducts. Without a filter, dirt, dust, and other impurities could collect inside the furnace, causing potential problems, including fire hazards.

When the filter gets too dirty, the furnace might work much more challenging to compensate for the deficiencies. If heating bills appear high for “no reason,” the reason may be a dirty filter. Replacing the old filter should become a top priority.

A dirty filter might lead to the system automatically shutting off to avoid overheating. An overheated furnace could suffer a cracked heat exchanger, leading to repair bills. An overheating furnace that doesn’t shut off presents a serious safety hazard.

Installing the wrong sized filter or trying to clean and reuse an old filter could prove disastrous. Leave the job of dealing with a dirty filter to a professional.

Is there any maintenance or repair work needed in Dallas, Fort Worth, or other local regions? The team at Air Patrol Air Conditioning could assist with inspections and fixes, as well as the installation of new systems.


Even when someone changes the filter on time, a system could collect a great deal of dirt and grime. Dirty furnaces don’t always perform well, and they raise safety and health concerns. A thorough cleaning, one that also includes the ducts, could help eliminate some issues.

Do-it-yourself vacuuming and cleaning plans might not be sufficient. A thorough cleaning relies on experience and the right tools. Consider that another reason to work with a professional service.

Be aware that anything that puts strains on the furnace does more than “merely” drive up energy bills. The various parts might suffer from strain and prematurely wear down. A warranty won’t likely cover replacement costs, meaning the homeowner must pay for the repairs. Preventive maintenance, such as cleaning the furnace, could eliminate both repairs and expenses.


Air blowing out of the vents at room temperature won’t help much on a cold winter night. If the furnace isn’t blowing hot air, the system mostly drains energy and makes noise. Fixing the problem could involve little more than checking the pilot light and the thermostat setting.

If the pilot light goes out, the burners won’t ignite. Without the fire from the burners, the furnace can’t heat the air. Reigniting the pilot could fix the issue right away. However, some issues with the pilot, burners, and gas lines might require repair work. If not, safety issues may arise.

Is the thermostat set to “on?” When set at “on,” the fan will run and blow hot air even when the furnace does not need to produce hot air. Changing the setting to “auto” lets the fan circulate air when the furnace heats it.


Thermostats won’t last forever, and they may require replacing or upgrading. Some homes might have an old thermostat that is significantly outdated. Upgrading the old thermostat could be past due at many houses.

Batteries have a relatively short shelf life. Once batteries die, the thermostat won’t work. Sometimes, homeowners may think there’s a disastrous underlying issue that prevents a furnace from working. However, the “proper fix” may involve doing nothing more than replacing the old batteries with new ones.


As mentioned above, a furnace could turn off when overheating due to a dirty filter. The high-limit switch may shut off an overheating furnace when other reasons contribute to overheating. Regardless, getting a furnace safety inspected when it shuts off seems wise.

Other reasons might contribute to the furnace shutting down seemingly no reason. The issue could be with the flame sensor or even the thermostat. Speculating why a furnace keeps shutting off won’t help the situation, but a thorough inspection performed by a pro might. Someone needs to uncover the exact problem and then do what is necessary to fix things.


A furnace could produce all kinds of noises, and distinct noises might indicate different problems. A rattling noise may occur when parts are loose. When someone realizes one or more parts are loose, a quick call to a repair technician may follow. Unfortunately, not everyone understands a noise could indicate a problem. So, things don’t get fixed until much later, if at all.

A clicking noise may indicate something is wrong with the ignition components. A furnace won’t turn on until ignition occurs, so the igniter continues to click until the furnace starts. A clicking igniter might be another problem homeowners dismiss since the furnace eventually starts. When the necessary parts die, the furnace may stay shut off. Also, gas could build up in the heater when it clicks without igniting. Such a situation might be highly dangerous since the gas is flammable and could explode.

Focusing on the specific noise might lead to guessing what the problem is. Whistling could indicate punctures in the ducts, and scrapping and banging might have entirely different causes. Guessing along is not enough, though. A trained technician must pinpoint the specific problem.


If a furnace uses flames to heat the air, why is there water near or around the system? Condensation produces the water, and a leak somewhere causes the water to exit. Damage or breaks somewhere in the system are often the cause of the leak. Holes in the humidifier would be one source of a leak, and problems in the condensation line could be another. Even plumbing lines unrelated to the furnace could lead to a leak.


Since leaks and other problems may result from many issues, having a professional inspect the system could be wise. Signing up for a thorough annual or semi-annual inspection may catch problems before they get worse.

We’ve been in business since 2003 and employ NATE-certified professionals. Besides furnaces, our team works on air conditioners and assists with indoor air quality work. Contact us at Air Patrol Air Conditioning to have a customer service representative schedule an in-home visit to your Forth Worth home for an estimate.