Gas furnaces always produce some noise when running. However, any loud or unusual noises can indicate that there is a problem with your furnace or blower fan. Some of these issues are fairly minor while others can be major safety hazards. For this reason, it is vital that you understand the issues that can cause furnaces to make loud noises and how they can be fixed.
1. Clogged Air Filter
If your air filter is clogged, it restricts the amount of air coming into your HVAC system. This can result in a whistling sound whenever your HVAC system runs. Luckily, this problem can easily be fixed simply by replacing the air filter. You can also prevent this problem by checking your air filter weekly and replacing it at least every 30 to 90 days.
2. Leaky Ductwork
If your ductwork is damaged or not properly sealed, it can cause the ducts to make loud rattling or banging noises. Air leaks can result in a pressure difference between the supply and return ducts, which can lead to loud noises coming from your ductwork. The same issues can also occur if your ducts have come loose and aren’t securely attached to the wall or ceiling. While these issues aren’t as serious as many of the others, it is still something that you should have inspected by an HVAC professional. This is especially true if your ducts are leaking since this can contribute to energy waste.
3. Worn-Out Bearings in the Blower Motor
Most heating systems use a direct-drive blower motor, which has bearings that power and turn the blower wheel to circulate air. These bearings should be lubricated every year to prevent them from drying out and making loud squealing or screeching sounds. The bearings can also wear out over time and cause the same type of noise.
The only way to ensure that the bearings are fully lubricated is to have your heating system professionally maintained every year. If you don’t, then the bearings will wear out much quicker, and you’ll need to have the blower motor replaced.
4. Worn or Misaligned Blower Belt
Older blower fans use a belt to drive the motor instead. As the belt ages, it can start to fray or move out of alignment. This also results in a loud squealing noise. This problem is easy to fix. Have an HVAC technician replace or realign the belt. If you do still have a belt-driven blower motor, you may want to consider upgrading to a new direct-drive blower in the near future.
5. Loose Blower Wheel
An HVAC blower fan circulates air by spinning a metal blower wheel. Age and general wear and tear can sometimes cause the wheel to move out of alignment or the fan to come loose from its housing. These problems can cause the blower wheel to scrape against the housing and result in loud, metal-on-metal grinding noises. This is something you will want to have checked out immediately as it could quickly ruin the blower fan.
6. Dirty Furnace Burners
In addition to lubricating the blower motor, you also need to have the furnace burners cleaned every year. This is yet another reason why annual furnace maintenance is so important. If the burners get dirty, it can lead to a slight delay before the burner ignites the gas. When this happens, the combustion chamber can fill up with gas and cause a loud explosion or boom when the burner ignites. This issue needs to be taken care of immediately as it could ruin your furnace altogether.
7. Cracked Heat Exchanger
This is the one problem that you really want to avoid. The heat exchanger works to transfer heat energy into the air inside the furnace, and it also seals off the combustion chamber to prevent carbon monoxide from escaping. If the heat exchanger is cracked, carbon monoxide can flow out into the air handler and be circulated throughout the building.
When too little air flows into the furnace due to ductwork issues or a dirty air filter, it causes excess heat to build inside the combustion chamber. This high heat can eventually crack or warp the heat exchanger. This problem is fatal and will require the furnace to be replaced.
A cracked heat exchanger often results in loud rattling sounds coming from the furnace. Due to the potential for carbon monoxide poisoning, you should immediately shut off your furnace if you hear loud rattling noises. Leave it off until it can be professionally inspected.
At A To Z Dependable Services, our highly skilled HVAC technicians are here to help you overcome any furnace issues. We work on all brands and types of furnaces as well as air conditioners, and we can also help with furnace and AC replacement. Moreover, our team specializes in a range of sewer and plumbing services for residents in the Niles area, including drain and septic cleaning, sewer and plumbing repairs and sump pump services. For more information or to schedule a furnace inspection, contact A To Z Dependable Services today.