Don’t Ignore These Noises From Your HVAC System
At Carrier Northwest, we love the sounds of a Pacific Northwest summer—except for the noises you might hear from your AC or heat pump this time of year. Maybe it’s a faint click, metallic scrape, or a rumble you notice while watching a Mariners broadcast or barbecuing with your family.
Your first instinct might be to ignore it, but wishing HVAC noises away won’t make them disappear.
Investigate HVAC Noises ASAP
Think of your HVAC equipment the way you think of your vehicle. If the engine started knocking or the brakes squealed, you’d see a mechanic ASAP to protect your safety and your car.
Use the same logic with your AC unit or heat pump. Noises can indicate mechanical or electrical trouble that, if left alone, can lead to a breakdown and a huge repair bill.
A Carrier Factory Authorized Dealer can diagnose your system’s noises and repair any issues before they worsen. Our Carrier Northwest online directory lists dealers throughout Oregon, Washington, and Montana.
Find a nearby Carrier dealer for tune-ups, repairs, diagnostics, or to upgrade your HVAC equipment. Click our dealer link to get started.
Meanwhile, you can do a little DIY troubleshooting to get an idea of why your HVAC sounds odd. Let’s break down exactly what your system is trying to tell you.
Air Conditioning’s Summer Warning Signs
When outdoor temperatures are consistently high, your AC likely works overtime. Listen for these unusual sounds:
Your AC Sounds Like Metal Scraping Metal
If the scraping sound continues throughout your AC’s run, the fan motor blade in the outdoor unit may be loose or bent, striking its surroundings like shrapnel. It could also mean the motor bearings have failed.
Shut the system off at the thermostat right away. A loose fan blade can snap off and destroy the condenser coil, turning a minor repair into a total system replacement.
Leave the repairs to the pros.
Your AC Buzzes When Starting
A brief, intense buzz at startup may indicate a failing capacitor. A stuck compressor relay might also be the problem.
In either case, you’ll want to schedule service soon. If you run your AC, the failing capacitor will strain your compressor. If the unit buzzes and won’t start, turn it off immediately and call an HVAC professional to diagnose and correct the issue.
What Your Heat Pump Is Telling You
Heat pumps are under significant mechanical stress because they operate year-round to heat and cool your Northwest home.
Your Heat Pump Rattles
A brief rattle as the heat pump powers down is normal. However, if that rattle persists while the unit is running, it usually points to loose hardware, an unbalanced fan, or loose refrigerant lines vibrating against the outdoor cabinet. It might also be a loose cabinet door.
Schedule an inspection, but be aware that unsecured vibrating copper lines can wear thin after continuous rubbing and may leak refrigerant.
Check around the heat pump and on its exterior cabinet for loose panel screws. Tighten them with a screwdriver. The fix may clear up the rattle.
When Your Furnace Makes Noises
Your furnace does not get a free pass in the summer. If you have a split AC system, your furnace’s blower motor runs whenever your AC kicks on. It plays a main role in distributing conditioned air throughout your home.
Don’t ignore a furnace making noise just because it’s summer.
Your Furnace Screeches or Squeals While Running
This high-pitched noise is almost always the indoor blower motor belt slipping, fraying, or completely drying out. In newer, beltless systems, the bearings inside the blower motor are failing.
Shut down the system immediately and call your local Carrier dealer. If the belt snaps or the bearings seize, the motor stops spinning. Without airflow, your indoor AC coil will freeze, and the outdoor compressor may overheat.
Your Furnace Emits a Loud Boom When Starting
Looking ahead to the fall, when you fire up your furnace, listen for loud pops or booms. Delayed ignition, when gas builds up before the burner ignites, can cause these sounds of a mini-explosion.
Turn off the thermostat, flip the furnace switch off, and shut off the gas valve. Call your local Carrier dealer for a professional inspection and diagnosis. Delayed ignition can cause your heat exchanger to crack over time, putting you at risk of carbon monoxide poisoning.
Ductwork Makes Sounds, Too
Summer HVAC sounds may originate from your ductwork, not your heating and cooling equipment.
When the blower motor kicks on, it can create a sudden pressure drop that moves the metal ductwork walls inward and outward, creating a loud bang.
Schedule a routine inspection to help resolve the issue.
Your Furnace Whistles Continuously
Your system may be gasping for air if it tries moving air through a small gap, creating a whistle.
Check your air filter. A heavily clogged air filter forces the system to suck air through any tiny crack in your return vents. Replace the filter and check air vents throughout your home, ensuring they are open.
ENERGY STAR® also recommends sealing and insulating air ducts to improve your HVAC system’s efficiency by up to 20 percent.
Prevent Noises With Maintenance
Prevention is the best way to manage HVAC noise problems. Schedule an AC or heat pump tune-up with your local Carrier dealer.
A professional technician will lubricate those dry bearings, tighten those loose panels, test your electrical capacitors, and catch vibrating refrigerant lines before they ever have the chance to start making noise.
A summer tune-up keeps your system quiet, lowers your monthly energy bills, extends the lifespan of your investment, and prevents minor issues from becoming costly breakdowns.
Find Your Local Carrier Dealer Today!
Don’t wait for a total HVAC breakdown when your heating and cooling equipment begins to emit unusual sounds. Whether you are in Portland, Central Oregon, the Puget Sound, or Billings, MT, you’ll find a top-tier Carrier dealer in our Carrier Northwest directory.
Your local Carrier expert has the training, experience, and diagnostic tools to pinpoint the source of the noise and restore peace, quiet, and comfort to your home. Locate a Carrier professional by clicking our dealer link.