When the temperature drops in Mississauga, the last thing you want is a furnace that won't start. A bit of preventive maintenance in the fall can prevent a very expensive (and uncomfortable) breakdown in the middle of winter.
Here are 7 furnace tune-up tips from our licensed technicians at Queensway Heating and Cooling.
1. Replace or Clean Your Air Filter
A clogged air filter is the single most common cause of furnace problems. A dirty filter restricts airflow, forcing the furnace to work harder — which increases wear and energy consumption, and can eventually cause the system to overheat and shut down.
How often: Every 1–3 months, depending on filter type and household dust levels. Homes with pets or allergy sufferers should lean toward monthly replacement.
2. Test Your Thermostat Before You Need It
Switch your thermostat to "heat" and set it 5°C above the current room temperature. The furnace should fire up within a minute or two. If it doesn't, you may have a thermostat issue, a blown fuse, or a tripped circuit breaker — easy fixes if caught early.
3. Check Your Vents and Returns
Walk through your home and make sure all supply and return air vents are open and unobstructed. Furniture placed over vents, closed registers in unused rooms, or blocked cold-air returns all disrupt airflow and reduce efficiency.
4. Inspect and Clean the Area Around the Furnace
Clear a 1-metre radius around your furnace of any flammable materials — cardboard, paper, paint cans, rags. Also check that nothing has been placed against or on top of the unit since last winter.
5. Check Your Pilot Light or Ignition System
Older furnaces have a standing pilot light that should burn steadily blue (or blue with a small yellow tip). A yellow or orange flame can indicate a combustion problem. Modern furnaces use an electronic ignition — if it's not clicking or the furnace won't light, call a technician.
6. Listen for Unusual Noises
Run the furnace for a few cycles and listen. Banging, rattling, squealing, or rumbling sounds can indicate loose components, a dirty burner, or a motor issue. These are always easier and cheaper to fix before they become failures.
7. Book a Professional Annual Tune-Up
A licensed HVAC technician will do everything on this list, plus check the heat exchanger for cracks (a cracked heat exchanger can leak carbon monoxide), test CO levels, inspect the flue, clean the burners, and calibrate the system for peak efficiency.
Most manufacturers also require annual professional servicing to keep the warranty valid.
Need a furnace tune-up in Mississauga or the GTA? Queensway Heating and Cooling offers annual maintenance plans starting at $12/month. Book your fall furnace tune-up today.