When your gas furnace starts acting up, it’s often at the worst possible time—like when a deep freeze hits Montreal, Laval, or the North Shore, and your heating system suddenly stops working. At AirGreen, we understand how essential a reliable HVAC heating system is during the long Canadian winters. This article is here to help you recognize the warning signs of an impending breakdown so you can act quickly, avoid expensive emergencies, and keep your family warm and safe.
Why it's critical to monitor your gas furnace
An aging or failing gas furnace can not only leave you without heat but also pose serious safety risks such as gas leaks or carbon monoxide emissions. Through our years of experience with HVAC maintenance and furnace repairs across the Greater Montreal Area, we’ve identified the most common early signs that a major malfunction is on the way.
1. Unusual or persistent noises
One of the clearest signs your gas furnace is in trouble is hearing strange noises. Clicking, humming, banging, or whistling sounds can point to:
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Worn-out or misaligned mechanical components
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A failing blower motor
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A buildup of dust or debris
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Combustion issues
AirGreen was recently called out for a service in Saint-Léonard, where a furnace was making a loud metal-banging sound. Upon inspection, our team discovered a misaligned blower motor that was close to damaging the bearing. A quick repair saved the homeowner from a complete breakdown during -20°C weather.
2. Unexpected increases in your energy bill
If your natural gas consumption suddenly spikes during winter without any changes in usage habits, your furnace might be running less efficiently. This could be caused by:
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A clogged heat exchanger
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Heat leaks in the ductwork
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An improperly calibrated burner
In Boucherville, we recently replaced a 20-year-old Lennox furnace. The homeowner had been complaining of sky-high heating bills. After installing a new high-efficiency Goodman model (AFUE 96%), the family reported a 27% drop in their annual heating costs.
3. Uneven heating across your home
If some rooms feel freezing while others are overheated, that could indicate:
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A failing blower fan
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Obstructed or poorly designed ducts
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An improperly sized or calibrated furnace
These symptoms are common in multi-generational homes or renovated houses, like those in Laval-des-Rapides, where duct layouts are often complicated. There, we installed a new modulating furnace paired with a zoning system, achieving perfectly balanced comfort in every room.
4. Yellow or unstable flame instead of a steady blue one
A steady blue flame indicates proper combustion. A yellow or flickering flame, however, may signal:
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Poor ventilation
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Soot buildup
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A carbon monoxide leak
This is a serious issue that can threaten the safety of your household. In Longueuil, we detected this problem during a routine annual maintenance visit. We shut down the system immediately, cleaned the burners, and adjusted the airflow, ensuring safe and healthy combustion.
5. Frequent need for repairs
If you're calling the technician more than once a season, it’s probably time to think about replacing your furnace. Signs your furnace is nearing the end of its life include:
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Outdated models with hard-to-find parts
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Repeated costly repairs
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Lifespan beyond 15–20 years
In Boisbriand, a homeowner contacted us after experiencing three breakdowns in just one winter. Instead of continuing to pour money into an unreliable unit, we installed a high-efficiency Bosch modulating furnace, reducing on/off cycles and significantly improving overall system efficiency.
Practical tips to avoid unpleasant surprises
At AirGreen, we strongly recommend the following actions to extend the life of your system and avoid emergency breakdowns:
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Annual preventive maintenance before winter hits
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Duct cleaning every 3 to 5 years
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Replacing your filter every 1 to 3 months depending on usage
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Monitoring your combustion flame regularly
We offer a comprehensive preventive maintenance program at competitive prices, covering all residential and commercial HVAC systems, including full diagnostics, tuning, and cleaning.
When should you consider replacing your furnace?
If you’re noticing multiple warning signs from the list above, it’s probably time to start thinking about a new installation. Modern furnaces offer:
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Energy efficiency up to 98%
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Eligibility for Hydro-Québec’s LogisVert rebates
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Quiet, stable, programmable operation
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Compatibility with smart thermostats
We recently installed a 60,000 BTU Goodman condensing furnace in a bungalow in Sainte-Rose, Laval, allowing the homeowner to qualify for a $1,800 grant, all while eliminating issues with inconsistent heating.
Why trust AirGreen for your HVAC heating needs?
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Regional expertise in Montreal, Laval, Longueuil, North Shore, South Shore
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Certified, skilled team that respects your schedule
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Personalized support from heat load analysis to after-sales service
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Products from trusted brands: Goodman, Bosch, Lennox, Trane
We don’t just swap out an old unit. We design long-term solutions tailored to your reality, and we guide you through every step to guarantee comfort, safety, and top-notch performance.
Conclusion
Don’t let your gas furnace fail you in the middle of a brutal Montreal winter. By staying alert to the warning signs, scheduling regular maintenance, and relying on a trusted HVAC expert like AirGreen, you can enjoy a warm, safe, and stress-free winter season.