From October to April the windows stay shut. Everything that happens inside, from cooking and showers to breathing, stays inside with you. Three different pieces of equipment deal with that, and they’re often confused.
The furnace filter: catches particles, adds no air
The filter sits where air returns to the furnace. It catches dust, pet hair and, with a better filter, finer particles. It does nothing about stale air, because it only recirculates what’s already in the house.
Two things decide how well it works: the filter grade, and whether it fits. A filter that’s too thin, or that leaves a gap at the edge, lets air go around it. That’s why we check the fit before we talk about upgrades.
Ventilation: brings outside air in
Fresh air has to come from outside. In a newer, tighter house, that’s a job for a ventilation system. In an older house, it leaks in on its own through the walls and windows, which also lets the heat out.
A heat recovery ventilator (HRV) brings fresh air in and pushes stale air out, and passes the outgoing heat to the incoming air on the way. The house gets fresh air without a cold draft and without throwing the heat away.
Which one your house needs
| What you notice | What it usually means | What helps |
| Dust comes back fast | The filter isn’t catching it, or doesn’t fit | Filter-fit review, better filter |
| Smells hang around | Not enough air change | Ventilation servicing, or an HRV |
| Stuffy by morning | Closed rooms, low air change | HRV, balancing |
| Dry all winter | Heated air with no moisture added | Humidity control alongside the ventilation |
What we measure
How air moves through the house, how the filter fits, whether an existing HRV is set up and running (many aren’t), and the humidity. You see the readings, then you decide.
Three levels
- Essential: airflow and filter-fit review, the right filter, ventilation servicing.
- Enhanced: better filtration plus fresh-air ventilation, set up and balanced.
- Optimum: filtration, ventilation and humidity working together, with controls, commissioned and explained.
Questions people ask
Do I need an HRV in an older house? Often not. Older houses leak enough air. A newer or renovated house with sealed windows usually does.
Will a better filter strain the furnace? A filter that’s too dense for the system can. We match the filter to the furnace.
What about an air purifier? It can help with particles in one room. It isn’t a substitute for ventilation.
Want to know what your house needs? Book a home visit at 587-792-1456.
See the Fresh air at home page
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Send someone our way and we pay you for it. Cash out in seven to fourteen days — no points, no credit against a future job.
- $100your first system referral
- $150your second
- $200every one after that
- $25any install, service or repair
System referrals apply to a complete heating and cooling system purchase. Terms and conditions apply.
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