Wildfire smoke could have impact on home, commercial HVAC systems and vehicles
With the worst of the drifting smoke from the Canadian and Minnesota wildfires seemingly in the rearview mirror — at least for the moment — Butler County homeowners and tenants can take the time to check on how the smoke may have affected their home air conditioning systems.
According to Mike Barnes, who teaches classes on air conditioning operations at Butler County Area Vocational-Technical School, your home’s air conditioning system should be relatively unaffected if you have good enough air filters and don’t leave your windows and doors open.
“In residential applications, the air conditioner only circulates what’s in the home itself,” Barnes said. “For the most part, it's a sealed system. No outside air comes into the house except through opening doors and windows. Most of what you see in the air is going to get filtered out through your filters.”
While wildfire smoke on its own might not cause damage to residential HVAC systems, the effects on air filters could cause your system to run less efficiently than before, leading to higher energy bills.
“Fine ash, soot and toxic particles can rapidly clog your air filters, restrict airflow and force the system to overwork,” said Chelsea Febinger of Shafer’s Heating and Air Conditioning in Kittanning. “Over time, these corrosive particulates can bypass your filters, contaminating your ductwork and damaging sensitive internal electronic components.”
In cases where wildfire smoke may have made its way into the home through open windows or doors, Febinger recommends the use of indoor air purifiers with HEPA-certified filters.
“In order to be HEPA-certified, the filters must be able to trap at least 99.97% of 0.3-micron particulate, a size that is particularly difficult to filter mechanically,” Febinger said. “Wildfire smoke is most akin to tobacco smoke, so it’s best to look for an air purifier with high tobacco smoke efficiency.”
While the impact of smoke on residential HVAC systems is expected to be minimal, larger commercial HVAC systems are a different story. According to Barnes, unlike residential HVAC systems which normally recirculate inside air, most commercial systems pull fresh air from outside the building during the morning hours through the use of an “economizer” — a system of fresh-air dampers.
“Most of our cooling in the morning hours comes from the outside air,” Barnes said. “After it gets to a certain temperature, those dampers close and it just circulates the air that's in the building, just like it would in your normal home. … The HVAC system actually physically pulling (smoke) in … is not possible in residential (systems). In commercial, it is possible with the way we've designed things and that's just to help keep costs down in commercial applications.”
However, as with residential applications, the same principles of filtration apply to commercial HVAC systems.
“Filtration is key in all HVAC applications, whether it’s with the smoke that we’ve had last week or with your standard day-to-day living,” Barnes said.
Barnes recommends commercial HVAC users change their air filters every three months. For residential users, that number may vary depending on certain factors.
“In residential applications, we like to tell folks, ‘If you don't have pets and you keep a clean home, every six months works,’” Barnes said. “’If you do have animals, you should change them every three months.’”
Similarly, most modern vehicles are equipped with cabin air filters that need to be replaced every so often. Unlike the typical residential HVAC system, most modern vehicles offer drivers the ability to either recirculate inside air or bring in fresh air from outside the vehicle.
Jerry Steiner, owner of Steiner’s Garage on South Chestnut Street, doesn’t believe the wildfire smoke will have much effect on the average car’s air conditioning system, assuming the car’s cabin air filter is doing its job.
“Maybe it’ll cause just a little bit of smell,” Steiner said. “Other than that, it's not going to affect much. All I'd recommend is putting a new cabin air filter in.”
