When your furnace stops working in the middle of a Durham Region winter, every minute counts. Emergency furnace repair in Oshawa is one of the most urgent home service calls there is — indoor temperatures can drop dangerously fast when it’s -15°C outside. Knowing what to do before a technician arrives can keep your family safer and may even help get your heat back faster. Here’s a practical guide to handling a furnace emergency from the moment you notice something’s wrong.
Step One: Assess the Situation Safely
Before anything else, determine whether you’re dealing with a furnace that’s not producing heat or a potential safety emergency. These require very different responses.
If you smell gas: Don’t touch any switches or try to troubleshoot. Leave the house immediately, don’t use your phone until you’re outside, and call Enbridge Gas at 1-866-763-5427 from a safe location. Only return when emergency services have cleared the building.
If your carbon monoxide detector is alarming: Get everyone — including pets — out of the house right away. Call 911 from outside. Carbon monoxide is odorless and colorless, and a furnace malfunction is one of the most common causes of CO buildup in Ontario homes.
If there’s no gas smell and no CO alarm, you’re likely dealing with a mechanical failure — uncomfortable and urgent, but not immediately dangerous. That’s when you can safely start troubleshooting while you wait for a technician from our furnace repair in Oshawa team to arrive.
Quick Checks You Can Do Yourself
Many furnace no-heat calls turn out to be simple fixes that homeowners can handle themselves. Before calling for service, run through these checks:
Check the thermostat. Make sure it’s set to HEAT, not COOL or OFF. Set the temperature at least 5 degrees above the current room temperature to trigger the heating cycle. If your thermostat uses batteries, replace them — a dead thermostat battery is a surprisingly common cause of furnace calls.
Check the furnace power switch. There’s usually a wall switch near the furnace that looks like a regular light switch. It may have been accidentally turned off. Make sure it’s in the ON position.
Check the circuit breaker. Locate your electrical panel and check whether the furnace breaker has tripped. If it has, reset it once. If it trips again immediately, leave it off and call for service — repeated tripping indicates an electrical problem that needs a technician.
Check the furnace filter. A severely clogged filter can cause the furnace to overheat and shut off as a safety measure. If your filter looks gray and matted, replace it with a new one and reset the furnace by turning it off at the power switch for 30 seconds, then back on.
Check for error codes. Most modern furnaces have a small LED light on the control board that flashes an error code when something goes wrong. The code legend is usually printed on the inside of the furnace door panel. Note the code and share it with your technician — it speeds up diagnosis significantly.
How to Keep Your Home Warm While You Wait
Once you’ve called for emergency service, focus on retaining heat in your home. The goal is to buy time until repairs are complete.
- Close off unused rooms. Shut doors to bedrooms, bathrooms, and spaces you’re not using to concentrate remaining heat in fewer rooms.
- Use electric space heaters safely. Plug them directly into wall outlets — never extension cords — and keep them away from curtains, bedding, and furniture. Never leave them unattended or use them in bathrooms.
- Layer up and insulate. Heavy blankets, layered clothing, and gathering the family in one room conserves body heat effectively.
- Let sunlight in. Open blinds and curtains on south-facing windows during daylight hours to capture passive solar heat.
- Block drafts. Roll up towels against exterior door bottoms and check that fireplace dampers are closed if the fireplace isn’t in use.
The TSSA’s homeowner resources include useful guidance on heating system safety and what to do during a gas appliance emergency in Ontario.
Our home heating solutions page also covers what to expect when scheduling urgent repair service and how our technicians prioritize no-heat calls during cold weather.
Common Causes of Emergency Furnace Failures
Understanding what went wrong can help you prevent the next breakdown. Here are the most frequent causes our technicians see on emergency calls in Durham Region:
Ignitor failure. The hot surface ignitor is a small ceramic component that glows red-hot to ignite the gas burner. It’s one of the most common failure points, especially on furnaces over 10 years old. Replacement is typically quick and affordable.
Flame sensor fouling. The flame sensor confirms the burner has lit. When it gets coated with residue, it can’t detect the flame and shuts the furnace off as a safety measure. Cleaning or replacing it usually solves the problem in one service call.
Inducer motor failure. The inducer motor vents combustion gases safely out of the home before the burner fires. If it fails, the pressure switch won’t allow the burner to ignite. This is a more involved repair but still a same-day fix in most cases.
Cracked heat exchanger. This is the most serious failure mode. A cracked heat exchanger can allow carbon monoxide to enter your home’s air supply. If a technician identifies a cracked heat exchanger, replacement of the heat exchanger or the entire furnace is required — this is not a repair to defer.
Control board failure. The circuit board controls every function of the furnace. When it fails, the furnace may show no signs of life at all, or may behave erratically. Replacement is usually straightforward with the right part on hand.
Frequently Asked Questions
How quickly can Fortis respond to a furnace emergency in Oshawa?
We prioritize no-heat calls during cold weather. Response times vary based on demand and time of day, but we make every effort to reach Oshawa and Durham Region customers as quickly as possible during heating emergencies. Call us at (289) 688-4822 and let us know you have no heat — we’ll give you an accurate ETA.
Will my home insurance cover emergency furnace repairs?
Most standard home insurance policies do not cover mechanical breakdown of appliances including furnaces. Some policies include add-on equipment breakdown coverage that may apply. Check your policy documents or contact your broker. If a furnace failure causes water damage (e.g., frozen pipes), that secondary damage is more likely to be covered.
At what indoor temperature should I consider evacuating my home?
If indoor temperatures drop below 10°C (50°F), especially with young children, elderly family members, or pets in the home, consider moving to a warm location such as a hotel, community centre, or friend or family member’s home while repairs are completed. Health Canada considers temperatures below 18°C (64°F) potentially harmful for vulnerable individuals over extended periods.
Should I try to restart my furnace multiple times?
You can attempt a single restart by turning the power switch off for 30 seconds and back on. If the furnace starts and then shuts down again, do not keep cycling the power — repeated restart attempts can sometimes damage components or, in rare cases, cause gas buildup. Call for service instead and let a technician diagnose the root cause.
When emergency furnace repair in Oshawa can’t wait, Fortis Heating & Air Conditioning is ready to help. Our TSSA-licensed gas fitters serve all of Durham Region, including Whitby, Ajax, Pickering, Bowmanville, and Cobourg. Call us now at (289) 688-4822 — we’ll get your heat back on as fast as possible.
