5 Secrets Your HVAC Technician Wishes You Knew
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After years of crawling through attics, squeezing into closets where the furnace barely fits, and hearing every rattle an air conditioner can possibly make, George Johnson, owner of Lee Air Services in Southlake, Texas, has learned that homeowners are trying their best when it comes to maintaining and operating their HVAC units. “But they’re doing a few things that actually work against their system,” he warns.
If you’ve ever wondered if you are making the right decisions about how you heat and cool your home, then keep reading to learn top HVAC tips from industry experts.
1. Closing some air vents doesn’t help.
It’s surprising how many people think closing vents in rooms they aren’t using saves money, says Johnson. “I understand why; it feels logical. But with modern HVAC systems, closing vents actually creates back pressure in the ducts,” Johnson explains. “That extra pressure can make your system run louder, cause duct leaks, wear out your blower motor, and make cooling and heating less even.” Johnson recommends keeping vents open.
What should you do? If you want to reduce energy use in certain parts of the home, the real fix is zoning or a smart thermostat, not choking off the airflow.
2. Frequent duct cleaning isn’t necessary.
Duct cleaning is another area that homeowners often misunderstand, says Josh Mitchell, HVAC technician with AirConditionerLab. He doesn’t recommend cleaning air ducts on a regular schedule. “In a typical home, ducts don’t fill up fast enough to justify frequent cleaning, so spending that money on better filtration or sealing air leaks often gives better results,” explains Mitchell. Plus, a clean filter does most of the work anyway. “If there’s visible debris, construction dust, pest activity, or mold, then it makes sense.”
What should you do? Johnson says: “If you change filters regularly and keep your outdoor unit clear, you can go several years without needing a cleaning.”
3. Not every noise is an emergency.
HVAC experts are often called to check out a noisy unit. As it turns out, many noises are perfectly normal.
Totally Normal Noises
- A gentle hum
- A quick “whoosh” when the system starts
- Clicking from the thermostat
- Light airflow sounds
What should you do? Johnson offers the following cheat sheet for when you hear a new worrisome sound coming from your HVAC unit.
Worrisome Noises
- Banging or clanking: Something is loose
- Screeching: Could be a blower motor or belt
- Buzzing: Electrical issues
- Gurgling: Low refrigerant or drainage trouble
- Loud pops in the ductwork: Pressure problems or loose connections
- Sounds like your AC is falling down a flight of stairs: Turn it off and call a pro right away
4. Don’t neglect your outdoor unit.
Many people forget to regularly check their outdoor HVAC units unless there’s a problem, which is a mistake. Johnson constantly finds outdoor units buried in leaves, weeds, mulch, ivy, and even patio furniture. “Your AC’s outdoor condenser needs breathing room,” explains Johnson. “If the fan can’t pull air in, the system overheats and your energy bills skyrocket.”
What should you do? His recommendation is to clear 2 feet of space around the unit. Once a year, spray the fins gently with a garden hose from the inside out to maintain the system. Just don’t use a pressure washer unless you want a very expensive repair.
5. The wrong air filter can strain your system.
Another common issue is choosing the wrong type of air filter for the unit. A lot of people think a higher MERV rating means cleaner air, so they grab the thickest, tightest filter on the shelf, but that isn’t the case, warns Johnson. “High MERV filters can choke airflow in systems not designed for them, which raises your energy bill and shortens the system’s life.”
What should you do? Johnson suggests sticking to MERV 8 to 10, which is the sweet spot for 90 percent of homes.
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