Why Do Some Heating Oil Systems Make a Lot of Noise?

Understanding What’s Normal—and What’s Not

Many of the sounds you’re going to hear from your heating oil system during the winter are perfectly normal, especially when it starts and stops running.

To give you a full picture, we need to divide this explanation into two parts, starting with heating oil furnaces. A furnace refers to the heating unit in a warm-air, or forced-air, system. After air is heated in the furnace, a blower forces it through ducts. The warm air is then released through vents or registers in your Michigan home.

To help you tell the difference between minor and major problems with your warm-air furnace, here is a list of common sounds you may hear. Please be aware that these are general guidelines provided solely for educational purposes. A correct diagnosis can only be made after a system inspection by a heating oil service professional.

• Humming: This usually comes from the transformer; all transformers hum to some degree. If the humming begins to increase, it’s an early signal that the fan motor may be wearing out. Immediate attention is not needed but an inspection should be done soon.
• Scraping: This often happens when the bearings in the blower motor wear out. If you hear this noise, shut off the furnace at once to avoid further damage. Then call your heating oil service company.
• Squealing: If it’s an older furnace, the blower motor may need oil. There may also be a loose belt.
• Vibration: The blower wheel or motor may need to be rebalanced.
• Whistling: This noise could mean that a dirty filter is limiting air flow. All warm-air systems have an air filter to screen out dust and other impurities. In general, you should check the filter’s condition a few times during the heating season and change or clean it when necessary. Refer to your owner’s manual for instructions or contact your heating oil service provider if you’re not familiar with this procedure.
• Popping: Abnormal air pressure makes ducts pop in and out. This can be caused by a clogged filter, an undersized or flimsy duct, or closed vents.
• Creaking: When air gets forced through your ductwork, you may hear a creaking noise because the ducts are expanding and contracting. This usually doesn’t happen with a properly installed variable speed system. There will be reduced air turbulence because the system doesn’t “blast” on and off.

Noises You May Hear from a Boiler System

In Michigan, some people may have a hot water (hydronic) system. To deliver heat to your home, water circulates around your boiler’s combustion chamber. A circulator pumps the hot water through pipes to heat baseboards or radiators. Eventually, the water returns to the unit to begin the cycle again.

Steam boiler systems work similarly except they generate steam, which rises to radiators (no circulators are needed). A low water cut-off shuts down the boiler if water levels drop too low, preventing boiler damage.

A noisy boiler can be a fairly common problem for people who have a closed loop hot water boiler. Like a radiator in your car, your boiler is filled with water. But if air leaks into the system, the pressure rushes through the pipes. This results in a banging noise.

This happens because air can be drawn into the system in several different ways. This includes a defective valve, a broken bleed screw, a pressure leak, or earlier repairs done to piping.

Another possibility is a problem with the expansion tank. Because water expands when heated and contracts when cooled, extra space is needed to store air. This is called an expansion tank. But air can be drawn back into the boiler from this device.

Get Professional Repair Service If You Have Concerns

If you have any concerns about whether your boiler or furnace is working properly, please reach out to your trusted Michigan heating oil service provider to request an inspection and evaluation of your heating oil system. Never try to make a repair on your own because you may cause further damage or create a safety risk.

If your boiler or furnace requires an expensive repair, you may want to explore new heating oil system options for your Michigan home. Your heating oil equipment service provider will be happy to help. Please remember to ask about any rebate opportunities available in Michigan for new heating oil equipment.