9 Essential HVAC Maintenance Tips for a Long-Lasting Unit

Gemma Johnstone
Written by Gemma Johnstone
Updated September 30, 2021
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Photo: Monkey Business / Adobe Stock

Give your HVAC some TLC

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Basic regular maintenance can keep your HVAC system running smoothly, minimize repairs, improve air quality, and reduce monthly energy bills. It can also increase the lifespan of your unit, giving you more time before facing the high cost of installing a new HVAC system.

Check out these maintenance tips you can carry out yourself, and when you should call in a pro for regular servicing.

1. Replace the Air Filters

You should replace the air filters at least every three months, but they may need replacing monthly during periods of heavy use. Dirty filters slow airflow, causing your system to work harder to maintain your desired temperature. Dust and debris buildup can also lead to expensive repairs and reduce the unit’s longevity. Houses with more family members and pets will probably need more regular filter changes.

2. Don’t Neglect Vent Cleaning

Something as simple as vacuuming the HVAC vents can help prevent dust and dirt buildup, which causes airflow issues.

3. Keep the Outside Unit Clean

The HVAC’s outside unit and heat pump can be easy to forget, but keeping them clean and free from debris is just as important as it is for the inside components.

Ideally, there should be at least 2 feet of clear space around the unit, free from shrubs and other vegetation. You should carefully wash off any dirt from the unit.

Pro tip: Although you can cover an outdoor air conditioning unit to keep it free from ice during the winter, heat pumps must remain uncovered.

4. Check the Condensate Drain

If you live somewhere with high humidity, you’ll probably have to deal with a clogged drain line at some point. Both furnaces and air conditioners have condensate drain lines, and a qualified engineer can confirm the location for you. Moisture can accumulate in these lines, becoming a breeding ground for mold and algae.

You can rinse the pipe with a vinegar-water mixture to keep it clean, plus wipe down any extra moisture with a cloth at the drain line’s entry. A bleach rinse can be effective for a heavier buildup. Ensure there are no cracks in the pipe, as this can lead to the water or cleaning solution leaking into the house.

5. Check Ducts for Leaks

You can lose as much as 30% of the air moving through the ducts in your home due to leaks and poor connections.

Regularly inspect the ducts in your garage, basement, attic, and crawl spaces. If there are any obvious leaks, seal them using mastic or foil tape. (Ironically, duct tape isn’t strong enough to provide a reliable seal.)

For any major problems with the ductwork, consult with a local HVAC engineer.

6. Is the Furnace Flame the Right Color?

A quick check of your furnace’s flame when it turns on is something that could help prevent an emergency—it should be pure blue. If the flame has streaks of yellow or orange, there may be combustion issues, and you should call out an engineer to inspect it.

7. Keep Your Unit Level

If your HVAC unit has moved and is sitting on an uneven surface, this lopsided position could cause problems with refrigerant levels, and the condenser or compressor could break. Regularly check to make sure it’s sitting level.

8. Don’t Use the System When Not Needed

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Photo: New Africa / Adobe Stock

Program your thermostat so you don’t need to keep adjusting the settings. Constant adjustment will make your system work harder, and having it on when you don’t need to can increase your energy bills and reduce its overall lifespan.

It’s also a good idea to turn off the water supplied to your furnace’s humidifier if you don’t use the heating during the summer.

9. Book an Annual Service With a Professional

While there are simple steps you can take throughout the year to keep your HVAC system running smoothly, these units are complicated pieces of technology. It's best to leave some aspects of their maintenance to the professionals. The pros can check refrigerant levels, clean coils, inspect elements like the furnace, electrics, thermostat, and more. Hiring a qualified local HVAC engineer to conduct an annual inspection and service is always a good idea.

Doing this can reduce the chances of having unexpected and costly repairs further down the line, and it provides peace of mind in terms of safety and maximizing energy efficiency.

In between services, if you hear strange sounds coming from your AC or you suspect there’s a problem with your HVAC system, don’t delay in calling in the pros. Otherwise, the repair could end up even more costly. If you have worries about the cost of an unexpected bill, you could consider an HVAC maintenance plan.

Preventative maintenance and proper HVAC installation could save you as much as 30% on your energy bills, and simple problems with airflow can result in your system being 15% less efficient.

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