Most furnace repair jobs are best left to a professional. However, knowing the causes and symptoms of furnace problems can help you identify when it is time to call a technician. Here are four common causes of furnace problems.
Airflow and air pressure in your HVAC system are carefully balanced for the size and heating demands of your home. A blockage inside your furnace or ductwork can lead to a pressure imbalance and serious problems, such as a cracked heat exchanger.
While some airflow blockages can be caused by natural dirt and dust buildup, there are a few mistakes that homeowners often make that can lead to a blockage. One example is closing the vent registers in the rooms in your home that you aren't using. This can actually reduce the efficiency of your system, as your furnace will still try to circulate the same amount of air through your home.
Another way that homeowners unknowingly block their furnace airflow is by neglecting furnace filter maintenance. It is a good idea to inspect your furnace filter once a month and clean or change it if it is covered in a thick layer of dust.
There are several parts inside your furnace that are in constant motion while the furnace is running. Unfortunately, constant motion also means eventual wear and tear. The motor, belts, and bearings in your furnace are the parts that are likely to malfunction first. While it is sometimes possible to replace these individual components, you should expect a full furnace replacement if your furnace is nearing the end of its average lifespan of 15 years.
Excessive noise during operation is the most noticeable sign of mechanical wear inside your furnace. The type of noise you hear can give a clue as to which part of your furnace is experiencing problems. Worn belts and bearings will usually make high-pitched squeaking or squealing noises. If you are hearing a low grating or grinding sound, it is likely that the blower motor is going bad.
The ignitor is the most important part of gas and oil furnaces. The ignitor creates the spark that burns your furnace's fuel to heat the air that comes into your home. If the ignitor has failed but your furnace blower motor is still working, you will find that cool air comes out of your vents when you turn on the furnace at the thermostat.
Ignition problems are usually caused by a failed ignitor switch or ignitor control board. Replacing these components is best left to a professional, but cleaning or changing your furnace filter regularly will help to prolong their lifespan by preventing dust from settling on them.
Inadequate Gas Supply
Like airflow and air pressure, the gas supply is another delicately balanced aspect of your furnace. Corrosion buildup, cracks inside the furnace, and kinks or blockages in the supply line are all problems that could prevent your furnace from heating properly.
A visual inspection is the best way to determine if there are gas supply issues with your furnace. The first place you should look is the pilot light. If the pilot light won't come on, there is obviously a problem, but a low-burning or yellow pilot light is a more subtle indicator of inadequate gas supply.
After inspecting the pilot light, you can look for corrosion and kinks on the outside of the gas supply line. Even if you think you have detected the source of the problem, you should never try to service the supply line yourself. There is a serious risk of exposure to toxic fumes when working on a furnace supply line, so this is a job that is best left to a trained technician. This is also a case where you should contact a technician as soon as possible to repair the problem before a major gas leak occurs.
Keep these signs of furnace trouble in mind so you can have your furnace serviced by an HVAC company like Getzschman Heating, LLC as soon as possible and keep it running smoothly for years to come.