Fall Furnace Checklist: What You Can Check Before the Technician Arrives

With Ontario winters being what they are, a working furnace isn't optional, and a little attention before the cold weather sets in can catch small problems before they turn into a cold house or, worse, a safety issue. This checklist covers what's safe and reasonable for a homeowner to check. Anything involving the burner, gas line, or venting should always go to a licensed heating technician.

Signs it's time for your pre-season check

• Heating season is approaching, or the system has been idle over the summer
• The furnace sounds noisier or different than it did last winter
• Airflow feels weaker in some rooms than others
• It's simply been a while since the last professional service

What you can check yourself

• Replace or inspect the furnace filter -- a grey, clogged filter restricts airflow and makes the system work harder. Check the arrow printed on the filter frame to make sure a new one goes in facing the right direction
• Walk around and make sure return grilles and supply registers aren't blocked by furniture, rugs, or boxes -- airflow needs a clear path in and out
• Vacuum the dust that collects around (not inside) the furnace, and clear away anything flammable stored nearby, like boxes, paint cans, or cleaning supplies
• Take a flashlight and look at any visible venting pipe for obvious corrosion, disconnection, or damage -- look only, don't touch or adjust it
• Test your smoke and carbon monoxide alarms using their test buttons, and check the manufacture date on each -- most need replacing every 7 to 10 years even if they still seem to work
• Turn the thermostat up a couple of degrees to trigger a heating cycle, and pay attention to how long it takes to ignite, whether you notice any odour, and whether the system runs smoothly

Write down what you find, along with the date, in a small maintenance log or notebook. It's a helpful habit on its own, and it's especially useful if a family member or new caregiver ever needs to get up to speed on the house quickly.

What should always go to a professional

Book an annual professional furnace inspection and tune-up -- this isn't optional maintenance, it's a safety check on a gas-burning appliance in your home. A technician will test the heat exchanger, combustion, and gas connections in ways that aren't safe or possible for a homeowner to check. If cost is a concern, many Ontario utility companies and municipalities offer maintenance plans or rebate programs that can make annual service more affordable -- it's worth a call to ask.

Mistakes to avoid

• Opening burner or blower access panels while the system is running
• Storing paint, cleaning products, or other flammable items near the furnace
• Ignoring a carbon monoxide alarm, even briefly, or assuming it's a false alarm without checking
• Treating a filter change as a substitute for a full professional inspection

When to call for urgent service

Shut the system off and call for urgent help if you smell gas or notice a burning odour, see soot around the furnace, experience repeated ignition failures, hear unusual banging or rattling, notice damaged venting, or if a carbon monoxide alarm goes off. None of these are things to wait out until a regular appointment slot opens up.