Losing heat is stressful, but what you do in the first few minutes often decides whether it’s a five-minute fix or a real repair. Work through this checklist before picking up the phone.
Start With the Thermostat
Newer Brampton homes are far more likely than older housing stock to have a smart or Wi-Fi thermostat, and those introduce their own failure points that a basic mechanical thermostat doesn’t have:
- Confirm it’s actually set to Heat and the target temperature is above the current room reading.
- If it’s a smart thermostat, check that it’s still connected to Wi-Fi — a dropped connection can leave some models stuck in whatever mode they were last in.
- Battery-powered units: swap the batteries even if the display still looks fine. A weak battery can power the screen but not the relay that actually fires the furnace.
Check the Breaker and the Furnace Switch
Furnaces run on a dedicated breaker, and it’s worth confirming it hasn’t tripped before assuming the worst. Most furnaces also have a wall-mounted switch near the unit that looks like an ordinary light switch — it’s easy for this to get bumped off during basement storage or renovation work and easy to overlook when troubleshooting.
Look at the Filter Before Anything Else
A badly clogged filter is one of the most common causes of a furnace shutting itself down as a safety measure, and it’s the cheapest thing on this list to fix. If it’s visibly packed with dust, swap it and give the system a few minutes to see if it restarts on its own.
Check for a Blink Code
Most furnaces built in the last 15 years have a small window that flashes an error code in a pattern of blinks. Photograph or video the pattern before you call — it tells a technician exactly what safety fault the system is reporting, which speeds up the visit considerably.
What Not to Do
Don’t open the furnace cabinet, don’t cycle the breaker repeatedly hoping it “catches,” and don’t touch anything related to the gas line or ignition assembly yourself. Repeated reset attempts on a system with a genuine fault can make the underlying problem worse, and gas components are legally restricted to TSSA-licensed technicians in Ontario.
When to Stop Troubleshooting and Call
If you’ve worked through the list above and the furnace still won’t run — or if you smell gas at any point — stop and call immediately. A Peel Region winter isn’t something to wait out overnight, particularly with young kids, older family members, or pets in the house.
Our dispatcher answers 24/7, and a technician can typically be on-site within 60 minutes.