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Summary

During fire season, wildfire smoke can significantly reduce indoor air quality by allowing fine particles and harmful compounds to infiltrate your home. Heat pumps themselves don’t purify air by default, they circulate and filter indoor air, but standard filters mainly catch larger particles like dust. To keep indoor air clean and healthy during smoke events, you can upgrade to high-efficiency filters, add HEPA or activated carbon systems, use UV-C lights, and adjust ventilation settings so you’re not drawing polluted outdoor air inside. Regular maintenance and the right air purification strategy help make your heat pump system part of a safer, cleaner indoor environment even when smoke outside is heavy.

How Can Heat Pumps and Air Purification Keep Your Indoor Air Clean During Fire Season?

Coastal living has many benefits, but one of the risks is the increasing threat of forest fires. Climate change is creating warmer, drier conditions in areas that typically didn’t see many forest fires previously. In addition, prolonged heat waves are causing extended fire seasons.

When an area experiences forest fires, there is the obvious issue of home destruction, but the lesser-known issue is how wildfire smoke affects the indoor air quality (IAQ) of your home.

It is important to have a heat pump system that can effectively purify indoor air, because if smoke gets in, it can cause a lot of damage and potential health issues. This post will cover risks associated with wildfire smoke, filtration options, and smart upgrades.

Wildfire Smoke & Air Quality

There is a common misconception that wildfires don’t affect coastal areas. While they may not be as common as in other areas, wind patterns can cause wildfires to spark on the coast. Wildfire smoke is made up of a mix of PM2.4 particles (small, inhaled deeply), volatile organic compounds (VOCs), and ash and soot. Even if your home seems to be airtight, smoke can get in through tiny gaps around windows and doors, HVAC systems, and cracks in the walls and foundation.

How Do Heat Pumps Interact with Indoor Air?

A heat pump interacts with indoor air a little differently depending on what mode is being used. In cooling mode, a heat pump absorbs heat from the air to cool your home. In heating mode, the pump releases heat into the air to warm your home. This is done using a refrigerant cycle. They don’t bring in fresh air from outside, but they do filter the air inside the home and circulate it.

Of note, heat pumps do not purify air by default. Standard filters only trap large dust/debris. If you want the air filtered, you will need to add on a purification system. Without this smoke particles from a wildfire will be continuously circulated throughout your home.

What are Air Purification Strategies for Heat Pumps?

The good news is that there are plenty of air purification strategies for heat pumps.

High-Efficiency Filters

High-efficiency filters will help to eliminate smoke and fine particles from the air in your home. You want to ensure you have a properly sized filter for your heat pump and make sure there is good airflow compatibility to avoid overloading the system.

If you aren’t sure if your heat pump can handle a certain filter, you should start by consulting the manual that came with the system. If you are unable to ascertain it that way, you can try putting one in and assessing a few factors.

• Does airflow seem to be restricted?
• Is your system running more than normal?
• Are you noticing warmer or cooler temperatures than normal?

If any of those points apply, then your system is too restricted, and you should try another filter option.

Add HEPA Filtration Units

High-efficiency Particulate Air (HEPA) filters are used to remove airborne particles from your home. HEPA filters can remove at least 99.7% of pollen, bacteria, dust, mold, and other air particles that are at least .3 microns. Typically, a HEPA filter does not replace the standard filter in your HVAC system. They are usually placed in a bypass configuration along the return air ductwork.

You have two options for HEPA filters. You can invest in a whole-house HEPA unit that will integrate with your existing HVAC system, or you can get standalone room HEPA purifiers as a supplement. If you are only having issues in a room or two, standalone units may be enough. However, if you are struggling with filter issues in your entire home, a whole house unit would be better.

UV-C Lights

UV-C lights are designed to neutralize biological contaminants like bacteria and mold. However, they are not effective against smoke particles on their own but are helpful when combined with other filtration measures.

Activated Carbon Filters

Activated carbon filters are great for dealing with VOCs and odours from wildfire smoke. They are frequently added as a secondary filter layer in advanced filtration setups.

ERVs/HRVs: What Role Do They Play During Fire Season?

Energy recovery ventilators (ERVs) and heat recovery ventilators (HRVs) are used to help filter the air in your home. During fire season, these units can bring in outdoor contaminants if they are not properly filtered. If your area is suffering a forest fire, you should shut off the ERV intake or use units that have filter upgrades and manual bypass settings.

Maintenance in Smoky Environments

If you live in an area that sees forest fires, it’s important to replace filters more often during fire season. Even if you are just nearby to a forest fire, the smoke can be carried by the wind and make its way into your home. Make sure you are cleaning ducts, coils, and fan blades after a smoke event. If you notice any airflow issues or a smell arises, you should schedule an HVAC inspection.

When Should You Consult a Professional?

There are certain situations where calling in a professional is the best choice. If you need help with any of the following, it’s time to schedule an appointment:

• Retrofitting air purification into older systems

• Choosing the right system for your home

• Compatibility checks for MERV 13+ filters

What’s the Bottom Line for Indoor Air Quality During Fire Season?

While some people believe that living near the coast means they won’t be affected by wildfires, that’s simply not true. However, a heat pump combined with smart air purification upgrades can help you maintain healthier indoor air and year-round comfort. At Coastal Heat Pumps, we’re happy to help, contact us today to learn more.

Frequently Asked Questions

Does a heat pump improve indoor air quality on its own?
Standard heat pump filters trap larger particles like dust, but they don’t fully purify air, fine smoke particles and VOCs often require specialized filtration upgrades.

What kinds of filters help with wildfire smoke?
High-efficiency filters and HEPA systems can capture very small particles like PM2.5 from smoke, and activated carbon filters help reduce odours and chemical compounds.

Should I run ventilation systems during fire season?
If outdoor smoke is heavy, turn off outdoor intake ventilation (like ERVs/HRVs) or use versions with filter bypass to avoid bringing polluted air inside.

Do UV-C lights improve air quality?
UV-C lights help neutralize biological contaminants like mold and bacteria, but they’re not effective alone at filtering smoke particles, they work best in combination with other filtration.

How often should I change filters in smoky conditions?
During fire season, replace or clean filters more frequently than usual to keep airflow strong and filtration effective, since smoke particles can clog filters faster.