Should I Repair or Replace My Furnace?
The furnace is acting up again — but is it worth another repair, or time to replace it?
It’s one of the toughest (and most expensive) decisions for Calgary homeowners, especially when winter’s already here.
In this guide, we’ll walk you through how to decide between repairing or replacing your furnace based on cost, system age, energy efficiency, and safety.
Because sometimes a quick fix makes sense — and sometimes it’s just throwing money at a dying unit.
Introduction
Few homeowner questions cause more head-scratching than this one: "Do I fix my furnace again, or is it finally time to replace it?" Repairs are cheaper in the moment, but at some point, replacement saves you more money, hassle, and cold nights. Let's break down the key factors that guide this decision.
Age of the Furnace
Most furnaces last 15–20 years with regular maintenance. After that, they become increasingly inefficient and prone to failure.
Under 10 years old?
→ Repair is usually the smarter choice.
10–15 years old?
→ It depends on condition, efficiency, and repair costs.
15+ years old?
→ Start budgeting for replacement, even if it's still running.

Pro Tip: Check your model and serial number — often, the manufacture date is hidden in the code.
Cost of the Repair vs Replacement
Use the 50% Rule:
  • If a repair costs 50% or more of a new furnace, replacement usually makes more sense.
  • For older units, even a repair that's 25–30% of replacement cost should make you pause.
Examples:
Energy Efficiency and Utility Bills
Older furnaces often run at 70–80% efficiency. Modern units hit 95%+ AFUE.
That means for every $1 of fuel, your old furnace wastes up to 30¢.
A new furnace could save 15–30% on energy bills every winter.
Utility rebates or government incentives can make the math even better.
Comfort and Reliability
Your comfort matters as much as your wallet. Signs your furnace may be past its prime:
Uneven heating
(cold bedrooms, hot living room)
Constant cycling
on and off
Unusual noises
(banging, squealing, grinding)
Frequent service calls
multiple times a season
If you're scheduling emergency calls more often than dentist visits, replacement is overdue.
Safety Concerns
This one is non-negotiable.
Cracked heat exchanger
A cracked heat exchanger can leak carbon monoxide dangerous and sometimes deadly.
Electrical issues
Electrical arcing or burning smells should never be ignored.
Red-tagged furnace
If a technician red-tags your furnace, it's time for a replacement. Period.
When to Repair vs Replace
When Repair Still Makes Sense
  • The furnace is under 10 years old.
  • Repair is relatively minor (<$500).
  • Efficiency is still decent and comfort is good.
  • Parts are readily available.
When Replacement Is the Smarter Play
  • Furnace is 15+ years old.
  • Repairs are frequent or costly.
  • Efficiency is poor and bills are rising.
  • Comfort problems persist despite tune-ups.
  • Safety issues are discovered.
Quick FAQs
Q: Should I replace my AC and furnace at the same time?
A: Often yes. Matched systems improve efficiency and can reduce install costs.
Q: How long does furnace replacement take?
A: Typically 1 day for a straightforward swap, longer if venting or duct upgrades are needed.
Q: Do new furnaces qualify for rebates?
A: Many high-efficiency models do. Ask your contractor or check local utility programs.
Conclusion & Call to Action
Repair or replace? The answer depends on your furnace's age, repair costs, efficiency, and safety. If you're spending big money on an old unit, replacement is usually the smarter investment.
Or check out our Quotes & Contractors FAQ to learn how to compare bids fairly.
About HVACHELP.pro
HVACHELP.pro stands as a dedicated online platform designed to empower Calgary homeowners with comprehensive resources and tools for all their heating, ventilation, and air conditioning needs. We understand that HVAC decisions, from routine maintenance to full system replacements, can be complex and costly. Our mission is to simplify this process, ensuring you make choices with confidence and clarity.
We provide unbiased information, practical advice, and local insights specifically tailored for Alberta's unique climate and housing demands. Whether you're troubleshooting a minor issue or planning a major upgrade, HVACHELP.pro is your trusted partner.
Informed Decisions
Gain the knowledge needed to confidently assess repair vs. replace scenarios for your furnace.
Maintenance & Upgrades
Discover best practices for furnace care and smart upgrades to enhance efficiency and comfort.
Replacement Guidance
Navigate the complexities of new furnace installations with our expert cost comparisons and insights.
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Access advice and resources specifically relevant to Calgary and Alberta home environments.
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