Yes, but only if it’s set up properly. Most residential systems can trap fine particles drifting indoors, but that depends heavily on the type of intake, the quality of the internal components, and whether the unit is maintained. Standard units often come with basic screens that do very little. Upgrading to a higher-rated option, like a MERV 13 or above, can make a noticeable difference in indoor air quality–especially on days when visibility outside drops and everything smells faintly of burning pine.
In older neighbourhoods, it’s common to see systems running with outdated or poorly-fitted components. I’ve seen houses where filters hadn’t been changed in years, and the indoor readings during nearby blazes weren’t much better than standing on the porch. It’s not always about buying the most expensive unit–it’s about knowing what it’s capable of and keeping it clean. Even the best system won’t help if the recirculation mode isn’t enabled or windows are left cracked open for fresh air that’s anything but.
What about portable units or those small window-mounted types? Mixed results. Some models offer basic particle screening, but many just circulate what’s already in the room. They might cool the space a bit, but they don’t do much to stop airborne contaminants from settling in your lungs. If you’ve got one of those running, it’s worth checking if it supports any upgraded filtration or can be used with external purifiers nearby.
During last August’s events, when the sky turned an eerie yellow for three straight days, our service line was ringing non-stop. People who’d never thought twice about this kind of thing suddenly wanted to know what they were breathing. There’s no perfect system, and results vary by layout, age of the building, and even how often doors are opened. Still, a properly maintained central setup, fitted with the right components and sealed tight, can give you a safer space to breathe when the outside air turns harsh.
How Central Air Systems in Calgary Handle Particulate Matter from Wildfire Smoke
Start with a high-MERV rated furnace filter–at least MERV 13. That’s the minimum needed to trap the fine particles that come with seasonal haze. Lower-rated filters won’t cut it; they’re better suited to dust and pollen, not the ultrafine stuff that gets into your lungs and stays there.
If your system supports it, a HEPA upgrade helps. Not all forced-air units can handle the air resistance HEPA filters create, though. It’s worth checking with a technician before installing one, otherwise, you might end up straining the blower motor. Been there–it’s not cheap to fix.
Don’t forget about recirculation settings. When the outside air quality tanks, it’s better to keep the system on recirculate. Pulling in fresh air through an HRV or intake vent can make things worse unless there’s additional filtration at those entry points. Some newer systems let you toggle this mode automatically, others might need a manual change.
Sealing and Duct Maintenance Matter More Than You’d Think
Leaks in ductwork, especially in basements or attics, let in unfiltered air. If the ducts haven’t been checked in a few years, chances are they’re letting contaminants bypass the filter entirely. A pressure test or even a smoke test (ironically) can reveal leaks you’d never find otherwise.
Also, dirty ducts can re-release particles long after the haze outside has cleared. If there’s any musty smell or visible dust blowing from vents, it might be time for a cleaning. But go easy on duct cleaning companies–some oversell. Ask for particle count data if you can. If a contractor can’t offer any numbers, they might just be guessing.
Something to Keep in Mind
Even the best setup won’t catch everything. You might still notice a faint smell or irritation if levels outside are extreme. Portable purifiers with true HEPA filters can help in bedrooms or offices. I’ve got one running beside my desk–doesn’t catch it all, but it makes the afternoons a bit more breathable.
What Types of HVAC Filters Can Capture Smoke Pollutants in Residential Units
Choose a MERV 13 filter or higher–that’s the short answer. These are rated to catch particles as small as 0.3 microns, which includes many of the harmful byproducts from combustion. For typical home systems, MERV 13 is the highest rating most units can handle without restricting airflow too much. Anything below that (MERV 8, MERV 10) might trap dust or pollen, but tiny airborne toxins? Not really.
If someone’s dealing with frequent poor air quality days, it might be worth looking into HEPA-level upgrades. These aren’t usually standard for furnaces or central setups, but there are bypass options or add-ons that can work alongside existing ducts. Still, that can get pricey, and it’s not plug-and-play.
Activated carbon filters offer another layer. They don’t trap particulates the same way, but they’re useful for reducing odours and volatile organic compounds that might sneak past even high-rated media. Not all homes need them–but if there’s a faint burnt smell lingering even after running the system for hours, carbon inserts could help.
One thing to watch for: not all filters labelled “high-efficiency” are clear about their actual rating. Always check the MERV number. Some marketing uses vague terms that don’t tell you much. If you’re unsure whether your current setup can support higher-rated options, it’s best to double-check with a tech. Better that than accidentally choking the airflow and stressing out the system.
When and How to Adjust Your Thermostat and Ventilation Settings During Smoke Advisories
Set your thermostat to recirculate indoor air instead of drawing fresh outdoor air. This reduces the amount of contaminated particles entering your home. Most modern systems have a “recirculation” or “closed” mode–engage it immediately once poor air quality alerts are issued.
Keep the temperature steady–around 20-22°C (68-72°F) is usually comfortable. Avoid lowering it too much just to feel fresher air; bringing in outdoor air can let pollutants inside, defeating the purpose.
Switch off any ventilation or exhaust fans that pull outdoor air in. This includes kitchen and bathroom fans unless they can be set to recirculate. Leaving them on can compromise indoor air purity by pulling in smoky air.
If your unit has a built-in filtration system, make sure to use the highest grade filter available. Change filters promptly if they show visible dust or clogging, as their efficiency drops over time.
On days with heavy particulate concentration, it’s better to keep windows and doors sealed. Even a small crack can let fine particles in, so double-check seals and close any gaps.
Sometimes, brief airing out can help if the indoor air feels too dry or stuffy–just choose moments when the outdoor air quality improves, like early mornings or late evenings. But, honestly, it’s a gamble and better avoided if you have respiratory issues.
For homes with smart thermostats, schedule automatic adjustments based on local air quality reports. It saves the trouble of remembering and can optimize timing to keep indoor air cleaner.
Finally, keep monitoring local air quality indexes. It’s tempting to assume all smoke-related hazards end quickly, but tiny particles linger and fluctuate throughout the day. Adjust settings accordingly–sometimes that means switching back to fresh air intake when the haze lifts, even if just for a short while.
Contact “Calgary Air Heating and Cooling Ltd” For More Information:
Address
95 Beaconsfield Rise NW, Calgary, AB T3K 1X3
Phone
+1 403 720-0003
Hours of operation
Open 24 hours 7 days a week