Do You Hear What I Hear? Don’t Ignore These Furnaces Noises

schedule HVAC maintenance

Live in your house long enough and you’ll get used to the sounds it makes. The hum of the refrigerator. The garage door opening. That one step that always creaks.

Then there are the sounds you don’t expect, like the ones that emanate from your furnace duct work. If you’re wondering when to schedule HVAC maintenance, it’s when you hear things coming from your furnace like:

  1. Rattling sounds

This sound can be unsettling, but it’s not an end-of-the-world HVAC issue. Rather, it’s a sign that your ductwork is either sized improperly or has simply come loose. When your furnace is firing, it will cause loose ducts to rattle against each other.

Again, it’s not a huge issue, but it is giving you a bigger energy bill, as loose ductwork can lead to a loss of heat.

  • Whistling

We might associate whistling with feeling carefree, but this sound coming out of your furnace is in fact more like wheezing, likely the result of a constricted air flow.

Look to see if you need to replace your filter. If that’s not the answer, check your vents to make sure they’re clear of debris. Like the rattling sound, it’s not a serious issue, but this could lead to bigger problems. Have your HVAC tech look at the furnace during scheduled maintenance.

  • Vibrating or humming

These noises typically signal a clog in the air flow return section of your heating system, which can lead to a massive drop in air pressure. The smaller the blockage, the longer the humming or vibrating noise will last. If you have a near-total blockage, it will announce itself with a short, loud, sudden hum.

  • Buzzing or scratching

In this case, you’ll need to call an exterminator rather than wonder when to schedule HVAC maintenance. The buzzing and scratching is probably mice, insects and other pests making a winter home in your ducts.

  • Squealing

When you hear a loud squealing coming from the engine of your car, it’s often a sign that one of the belts is about to give. The same is true for your furnace. A loud, persistent squeal can be a sign that the fan or motor belt is about to break and needs to be replaced as soon as possible.

  • Booming

This might be a serious issue. When you hear a soft, infrequent boom, you might be hearing the furnace plenum, its air distribution box, expanding.

However, a loud, frequent boom is the sound of a delayed furnace ignition, which can be a threat to the entire system. When you hear this sound, call your local HVAC expert as soon as possible.

Nearly any unusual noise from your system is your furnace telling you when to schedule HVAC maintenance. (One exception: a snapping and popping noise when your system turns on, which is just the sound of ducts expanding and flexing because of a change in air pressure.)

Do you need to schedule maintenance on your HVAC system? Are you hearing weird noises from your ducts? Talk to All Seasons Comfort Control. Our team can examine your heating system for problems, allowing you to rest comfortably all winter.