Why your old furnace is a hidden danger: Upgrade to a modern model

A new furnace can provide several benefits, including increased efficiency, better indoor air quality and reduced maintenance costs

ONE OF THE major headaches facing Canadian homeowners is aging furnaces, particularly in winters that require a heating system that is dependable, such as in Ontario, where winter is a major concern. Replacing that old model with a highly efficient one can not only cut bills but also increase safety and keep homes warm. This is why aged furnaces are unsafe and why upgrading in 2025, with the assistance of experts. Older furnaces (those older than 15-20 years) are not only inefficient but are considered a liability. It is precisely these types of furnaces that most often create situations where people need emergency furnace repair London. Don’t waste time and call Superior Plumbing and Heating. They will arrive on time and solve the problem of serious breakdowns.

Here is the reason why they are dangerous and expensive: 

• Disintegrated components: Gas lines and heat exchangers rust away with time, particularly in damp Canadian basements, and they create a risk of gas leak or fatal exposure to carbon monoxide (CO).
• Waste of energy: The efficiency of old furnaces only reaches 60 percent, wasting gas at a rate of up to $400-600 a year, compared with new models.
• High failure rates: The broken components are a common occurrence due to the highly worn-out motors or thermostats.
• No safety tech: Some older models do not have modern safety features such as flame detection, making it more likely that there will be unnoticed hazards.

The old furnace issues are not only technical, but they strike in real life. In the extreme temperatures of winter in Canada, a broken furnace translates to frozen nights and an insane bill. Consider a family in London last winter: their furnace, which was 22 years old, began to make strange hissing noises, and the pilot light was flickering in and out. Superior Plumbing & Heating were called in to have a look at the emergency. A broken heat exchanger that was leaking trace levels of CO was discovered by the technicians, a time bomb waiting to blow. And in a few hours, they installed a new, high-efficiency unit that reduced the family’s gas bill by 20%. That hasty solution also made a close call a brilliant investment, which is why an expert role is important.

Aging furnaces are a common headache for Canadian homeowners, especially in provinces like Ontario, where winters demand reliable heat. Swapping that outdated unit for a high-efficiency model can slash bills, boost safety, and keep homes toasty. Here’s why old furnaces are risky and why upgrading in 2025, with help from pros like Superior Plumbing & Heating.

Old furnaces, especially those pushing 15-20 years, are more than just inefficient—they’re a liability. Here’s what makes them dangerous and costly:

• Corroded parts: Gas lines and heat exchangers rust over time, especially in humid Canadian basements, risking gas leaks or deadly carbon monoxide (CO) exposure.
• Energy waste: With efficiency as low as 60%, old furnaces guzzle gas, inflating bills by $400-$600 a year compared to modern models.
• Frequent failures: Worn-out motors or thermostats break often, with repairs costing $250-$2,000 per incident.
• CO poisoning risks: Faulty venting or cracks can leak CO, which Health Canada says causes 80 deaths and 1,000+ hospitalizations annually in Canada
• No safety tech: Older models lack modern safeguards like flame sensors, increasing the chance of undetected hazards.

The problems with old furnaces aren’t just technical—they hit hard in everyday life. In Canada’s brutal winters, a failing furnace means freezing nights and skyrocketing costs. Take a Vaughan family last winter: their 22-year-old furnace started making odd hissing noises, and the pilot light kept flickering out. They called Superior Plumbing & Heating for an emergency visit. The technicians found a cracked heat exchanger leaking trace amounts of CO, a disaster waiting to happen. Within hours, they replaced it with a new, high-efficiency unit, cutting the family’s gas bill by 20% and qualifying them for a $600 Ontario rebate. That quick fix turned a near-tragedy into a smart investment, proving why professional expertise matters.

Why make the leap to a new furnace?

Modern models are built for Canada’s cold and offer benefits that old clunkers can’t touch:

• Top-tier efficiency: 95-98% AFUE ratings mean up to 35% savings on gas bills—hundreds of dollars annually in places like London Ontario.
• Safer operation: Advanced sensors detect leaks or CO, shutting down the system before danger escalates.
• Reliability: New parts mean fewer breakdowns, saving on costly emergency furnace repairs in Ontario’s deep freeze.
• Greener footprint: Lower fuel use cuts emissions, aligning with Canada’s 2030 climate goals.
• Smart controls: Wi-Fi-enabled thermostats let homeowners tweak heat from anywhere, maximizing comfort and efficiency.

A report from Natural Resources Canada (NRCan) found that heating accounts for 61% of household energy use in Canada, with old furnaces driving up costs and emissions.Heating in a typical Ontario home would be reduced by $500 a year by changing the model to high-efficiency. Pre-2005 installed old furnaces are a waste of energy and prone to issues such as leakage of gases. DIY fixes are a trap—tinkering with gas lines or vents without training can spark fires or worsen leaks. Professionals, equipped with tools like CO analyzers, ensure safe, code-compliant repairs or installations, saving money and stress. The tools available to professionals, such as CO analyzers, help to save money and stress by performing safe and code-compliant repairs or installations.

Why do these problems occur with an old furnace?

Deteriorated parts: Heat exchangers and gas valves wear out, particularly in damp cellars typical of Canadian houses, after 15 years or so. 

Poor installation: The fittings are loose or not well ventilated, usually due to hurried installations decades ago, which will burst under stress, leading to leakages. 

Maintenance failure: Not performing annual maintenance allows dirt to jam up burners or minor cracks to develop and cause gas or CO leakages. 

Strain during winter: The polar vortexes in Canada drop to -30 C in regions, which puts pressure on pipes, leading to cracks or contractions. 

Unknown problems: One of the furnaces had a damaged valve concealed in it that could cause CO to accumulate, but the professionals uncovered it in time.

Pro expertise: Experts verify pressure, vents, and exhaust, and no latent threats exist. To upgrade smartly, act now. Reserve a pre-winter check-up – in London Ontario, it is best in November.

To upgrade smartly, act now. Book a pre-winter inspection—October is ideal in Canada. Check for rebates through programs like ON Hydro or Enbridge. Size the furnace correctly; a pro can calculate your home’s needs. Quality installs prevent future headaches. Upgrading isn’t just a fix—it’s a lifeline for safe, affordable warmth through Canada’s coldest months, turning risky nights into cozy ones.