How to Maintain Your HVAC System

Pro working on AC unit

Regularly changing filters and basic cleaning help your cooling and heating system run more efficiently. My monthly HVAC maintenance takes about an hour (or less), which isn’t bad considering how expensive repairs can be.

Even though you can maintain most aspects of your HVAC system, a professional tune-up should still be scheduled to inspect all electrical connections and performance. Taking care of your HVAC helps it run better, saves you money, and means a longer-lasting, safer system.

Monitor and Change Air Filters 

Man changing HVAC dirty air filter
Photo Credit: steheap / Adobe Stock Free / License

This simple yet essential HVAC maintenance task is the best way to maximize your system’s efficiency. Check your air filter every few weeks to ensure it isn’t clogged with dirt and debris. Most filters need replacing every 60 to 90 days, but I change mine more often because I have pets.

Always switch off your system before swapping filters. The filters are usually behind the metal grilles in your walls or inside the air handler unit. Unscrew the cover or pull the tab to access it. 

My Tip: When you remove the old filter, pay attention to the direction in which your arrow is pointing. Then, put the new one in facing the same way. 

Clean Your Exterior Unit

Keep an eye on your outdoor HVAC unit because it can gather a lot of dust and leaves. I always try to keep the area clean by removing any debris and giving it a quick wipe.

Also, if you have bushes or any other plants close to the unit, trim them so the air can flow better. You want about two or three feet of free space on each side and at least five feet above.

Check Refrigerant Levels

If your HVAC’s refrigerant is too low, it won’t be able to cool the air that passes through the evaporator coil. 

Here’s what to check:

  • Warm air coming from vents
  • Higher energy bills than usual
  • Ice forming on the evaporator coils
  • Weak airflow from vents
  • Hissing or bubbling sounds (if there’s a significant leak)

To get the system working right again, contact an HVAC professional to recharge it. Don’t try to do it yourself — this is a job for the expert technicians. Refrigerant is a hazardous chemical that can cause burns and serious injury.

Clean Your Vents

Hands cleaning HVAC vent
Photo Credit: TRAVELARIUM / Adobe Stock Free / License

Most people think they need to clean their vents all the time for proper HVAC maintenance, but that’s not really true. According to the EPA, you only need to clean them when you notice:

  • Lots of dust blowing out when the air starts
  • Visible dirt or mold inside the vents
  • Strange smells from vents
  • Signs of bugs or mice

Here’s what to do: 

  • Turn off your HVAC system. 
  • Vacuum what you can see and wipe the vent covers with a damp cloth. Don’t try to clean deep inside the ducts yourself — this could damage your system or make air quality worse. 
  • If you see lots of dust coming from vents or smell something weird, it’s time to call a professional.

Turn Off Your Humidifier in Spring (If You Have One)  

If your home has a humidifier with your HVAC, you should turn it off when spring comes. Your AC already removes humidity from the air — that’s part of how it works. Running a humidifier simultaneously makes your AC work harder than it needs to and wastes energy.

Here’s what to do:

  • Switch off the humidistat (it’s usually near your thermostat or above the humidifier)
  • Shut off the water supply valve
  • Take out and clean the water filter
  • Move the damper to “SUMMER” 

Check if Your Exterior Unit is Level

An uneven outdoor HVAC unit can cause the motor to overheat and stop working in peak conditions, leading to costly repairs down the road.

You can check if your unit is level with a simple bubble level. Look at the top and sides of the unit — a few degrees off isn’t a big problem, but more than needs fixing. Also, check the concrete pad under your unit for cracks or if it’s sinking.

Inspect Evaporator Coils

Your AC’s evaporator coil is really important because it absorbs the heat from your home’s air. When it gets dirty or has problems, your AC works harder and uses more electricity.

You can look at the evaporator coil by removing the access panel on your indoor unit, but don’t try to clean it yourself — it requires special tools and expertise to clean properly without causing damage.

Here’s what to do:

  • Ice on the coil
  • Water leaking inside
  • Warm air from vents
  • Bad smells when the AC runs
  • Signs of rust or corrosion

If you spot something that doesn’t look right, call an HVAC professional to have it fixed. The best way to avoid these problems is to change your air filters often.

Check the Batteries in Your Carbon Monoxide Detector and Thermostat 

Bad batteries in your safety devices can be really dangerous for your HVAC system. You need to check two things:

  • Carbon monoxide detector: Test it every month (just press the test button) and put new batteries in every 6 months. If your CO detector isn’t working properly, it can’t warn you about dangerous gas from a broken HVAC system.
  • Thermostat: If you notice your thermostat display is blank or showing inconsistent readings, it likely needs new batteries. Dead batteries can cause your heating or cooling systems to malfunction, leading to higher energy bills.

Clear Condensate Drains

Water Dripping From AC Condensate Drain
Photo Credit: VPales / Adobe Stock Free / License

Your AC’s condensate drain is really important because it removes water that forms when your AC cools the air. If the drain gets blocked, water can back up and cause serious problems like water damage or a broken AC unit.

You can clean it yourself once a month — especially during peak season. 

Here’s what to do:

  • Turn off your HVAC system completely
  • Look for the condensate pan under your indoor unit
  • Check if there’s standing water in the pan (this usually means you have a clog)
  • Find the white PVC pipe near your indoor unit
  • Pour 1 cup vinegar mixed with warm water down the pipe
  • Wait 30 minutes
  • Rinse with clean water

Check Doors and Windows Frequently

When your doors and windows are not sealed right, you can lose a lot of heat or cool air. About 25 to 30% of the energy we use for heating or cooling our place can slip out through windows. 

Here’s what to do:

  • Look for gaps or feel for drafts
  • If you find any, seal them up with weather stripping or caulk

Schedule Professional Tune-Up

I schedule two HVAC maintenance check-ups every year: one in the spring and again in the fall before seasonal changes are underway. 

An HVAC technician follows a detailed checklist to ensure everything works properly. Some tasks are best left to specialists who know exactly what to look for and have the right tools. Don’t worry; Home Gnome can connect you with a pro near you.

Here’s what they’ll do:

  • Inspect the condenser, evaporator, and blower coils 
  • Check for any refrigerant leaks
  • Clean the drain lines and eliminate any clogs
  • Inspect all electrical connections
  • Recalibrate thermostats for optimal performance 
  • Check all gas connections (only for gas furnaces)
  • Inspect ductwork and registers for any blockage

Find an HVAC Technician Near You

Doing these routine HVAC maintenance on my system has saved me money and hassle. Sure, it takes some effort, but knowing these basics can really cut those bills down and keep the air in the house feeling the perfect temperature. Plus, your system will last longer if you take care of it right.

If you ever notice an issue or have questions, hiring the help of a trusted HVAC technician is always the right choice. Home Gnome connects you with the best local HVAC maintenance experts. They’ll handle any issues promptly, ensuring your system works smoothly all year round.

Main Photo Credit: Studio Romantic / Adobe Stock Free / License

Luminita Toma

Luminita Toma is a detail-oriented writer and home improvement enthusiast. When she’s not writing or tackling DIY projects — much to the amusement of her family — she’s exploring new places or catching a movie with friends.