What to do when the heat goes out (the next 30 minutes)

It's 9 PM, -14 °C, and your furnace just stopped. Here's what to do — and not do — for the next half hour.

The checklist

1. 1Confirm the thermostat. Battery-powered? Replace it. Display showing setpoint above current temp? Good — keep going.
2. 2Check the breaker. Furnaces have a dedicated breaker; sometimes a heavy load nearby trips it. Reset once. If it trips again, stop.
3. 3Look at the furnace switch. There's usually a light switch on the side of the unit or upstairs at the top of the basement stairs. It looks like a regular wall switch and it's often turned off by accident.
4. 4Check the filter. A black, fully blocked filter can trip the high-limit switch and shut the furnace down. Pull it. Try without it for 30 minutes.
5. 5Look at the front panel for blink codes. Most furnaces flash a code through a small window — write down the pattern (e.g., 3 short, 1 long).

When to call us

Anything you can't fix with the steps above. We answer 24/7 from November to March, prioritize seniors and households with young children, and bill the diagnostic fee against the repair. There's no premium for late-night calls — emergency rates are the same as daytime rates.

If you have a maintenance plan with us, you're at the front of the queue automatically. If you don't, we'll still come — but plan customers move first.

The 30-minute hold

Do not use a gas oven or barbecue for heat. Keep exterior doors closed, move people into one interior room, use electric space heaters only where the circuit can handle them, and keep anything flammable at least one metre away. Dispatch will give you the real arrival window when the call is assigned.