Few things can be more frustrating to a Houston homeowner than dealing with a malfunctioning furnace. However, the unfortunate reality is that every furnace will have an issue during its lifespan. Here are some of the more common furnace problems you might run into.
Thermostat Is Not Working
The thermostat controls the heating system, so it is vital in maintaining a comfortable home environment. If the thermostat breaks, you will notice when the furnace fails to turn on or off. Adjusting the temperature might yield no response. Another indication of a damaged thermostat is when the furnace short cycles, running briefly without completing an entire cycle. This not only makes your home uncomfortable but also escalates energy bills.
Furthermore, a malfunctioning thermostat can cause a disparity between the room’s temperature and the thermostat setting. For instance, you might set the furnace to 72 degrees Fahrenheit, but the room feels more like 90 degrees. Short cycling can particularly impact rooms farthest from the furnace, exacerbating heating and cooling issues. Another telltale sign of a faulty thermostat is if your programmable thermostat continually resets to factory settings.
A Problem With the Pilot Light
Older gas furnaces utilize a pilot light to ignite burners, producing a small blue flame. If the pilot light isn’t working, this flame will be absent, and your furnace won’t heat your home. Several factors can cause the pilot light to go out. Drafts or a broken thermocouple could be among these issues.
Inadequate insulation in your home might result in an air source near your furnace. Whenever a gust of wind occurs, it can extinguish the pilot light. Homeowners can relight the pilot light themselves, but if the problem persists, consulting our HVAC professionals at Mackey Services to evaluate the pilot light may be necessary.
Another common issue related to the furnace’s pilot light is dirt buildup in the gas intake valve. Without regular furnace maintenance, dirt can accumulate over the valve, restricting the pilot light’s oxygen supply. Fortunately, a trained HVAC technician can efficiently resolve this problem by cleaning the intake valve.
The pilot light’s thermocouple is a safety device monitoring the flame’s correct burning. If the thermocouple detects an issue, such as no flame or insufficient heat, it disconnects the pilot light from the gas supply to prevent leaks. A malfunctioning thermocouple can cause the pilot light to go out. Common thermocouple issues your furnace might experience include dirt affecting its sensing ability, displacement preventing heat reception from the flame, or damage. Regardless of the thermocouple issue, a professional HVAC technician is needed to diagnose and fix it.
A furnace issue may also involve the pilot light not generating sufficient heat. Even if the thermocouple is functioning correctly, a yellow flame that doesn’t produce enough heat may fail to trigger the thermocouple, leading to a disconnect in the gas supply to the pilot light. Resolving this problem is typically complex and requires the expertise of HVAC technicians. During a pilot light check, HVAC technicians can verify that your furnace isn’t releasing dangerous carbon monoxide, safeguarding your health and your family.
Cracked Heat Exchanger
The heat exchanger of your furnace heats the air flowing through the system. It consists of tubes and coils circulating airflow through the furnace to heat the interior. A crack in these tubes and coils can cause gases such as sulfur dioxide, carbon monoxide, and nitrous oxide, produced during furnace combustion, to leak into your home. These gases can pose serious health risks, including illness and even death.
If the tubes and coils of your furnace’s heat exchanger are cracked, you may notice carbon buildup or soot inside the stove. This occurs because the furnace isn’t burning cleanly, and the combustion cycle remains incomplete.
Damage to the heat exchanger can also manifest through stress cracks and signs of wear and tear on external furnace parts. These indicators suggest that internal components are experiencing similar wear and tear. If you find water on the floor at the base of your furnace, it signifies a condensation issue or a cracked heat exchanger.
A cracked heat exchanger emits unusual odors, resembling formaldehyde, which are unpleasant. Exposure to this odor can cause headaches, dizziness, or flu-like symptoms. Ignoring a cracked heat exchanger is not an option. It requires immediate attention from a trained HVAC technician.
Malfunctioning Blower Motor or Belt
If the blower belt experiences an issue, the vents in your system will likely produce loud noises. These noises can resemble squealing, rattling, or screeching sounds. Lubrication might temporarily mitigate the noise, but in most cases, problems related to the blower belt require attention from an HVAC service technician.
Another sign of a damaged blower belt is weak airflow or a complete lack of airflow. Regular maintenance by an HVAC professional can help identify potential blower belt problems before they adversely affect your furnace’s operation.
When the blower motor overheats, you may detect a burning smell. This occurs if the blower motor draws excessive amperage, causing the wiring to burn. While most modern furnaces shut down automatically in such situations, some may not. This is a potentially dangerous issue because it could lead to a fire. If you detect any burning smell, immediately shut off your furnace and contact a professional. Ignoring overheating could result in further damage to your furnace.
Limit Switch Malfunction
The limit switch is a small but essential component that keeps your home safe by automatically turning off your furnace if it gets too hot. The limit switch is typically found inside the cover panel of your furnace. Since the limit switch is designed to detect and shut down issues with your furnace, there are several reasons why it might trip. For example, an airflow problem inside your furnace could be caused by dirty filters, leading to overheating. A dirty temperature sensor on your furnace limit switch or a defective high limit could also be an issue. The best way to avoid these issues is to keep up with the recommended maintenance schedule from your furnace manufacturer.
Worn-Out Ball Bearings
Your furnace’s ball bearings are designed to allow the motor to move smoothly. Over time, they can wear out and require replacement. Damaged ball bearings could cause a scraping sound inside your furnace. If you hear a scraping sound, turn off your furnace immediately and have it inspected by a professional.
Other noises indicate issues with your furnace, including popping, rattling, or pinging sounds. Rattling sounds usually occur because a panel on your furnace is loose and needs to be tightened. A popping or pinging noise could be due to ductwork expanding and contracting based on whether you are pushing hot or cold air through the ductwork.
The Best Heating and Air Conditioning Services in the Greater Houston Area
At Mackey Services, we have kept Texas residents comfortable since 1992. We have a team of experienced, licensed, NATE-certified HVAC technicians. We are proud to be an A+ Better Business Bureau-accredited business.
Our services include HVAC repair, maintenance, and installation. We install mini-splits, perform indoor air quality testing, install smart thermostats, and work in residential and commercial settings. Our electrical services include electrical repair, ceiling fans, electrical panels, and EV charging stations. We offer various landscaping services, including property maintenance, irrigation inspections and repairs, and seasonal enhancements. Contact Mackey Services today, and see why we are considered reliable HVAC services for the greater Houston area.
