Decide whether to repair or replace

Start with a diagnosis, then compare the practical options and complete costs.

Reviewed 11 October 2026 · Canadian dollars where stated · Independent comparison guide

The answer in plain language

A furnace’s age is context, not a diagnosis or an automatic replacement deadline. Ask what failed, what evidence supports that conclusion, whether safe repair is available, and what the repair includes. A replacement proposal should explain the problem it solves.

Urgent safety comes before comparison

If a carbon-monoxide alarm sounds, leave the home and call 911 from outside. If you smell gas, leave immediately without operating switches or electronics and call the gas utility or 911 from a safe location. Do not use a buying checklist to delay that response or try to locate the leak yourself.

For a non-emergency comfort or no-heat problem, describe what you observed and when it began. Use the site’s safe-observation guide and qualified service. Do not repeatedly reset equipment or bypass a safety control to keep it running.

Make the repair proposal reviewable

Request a written diagnosis, the component or condition involved, repair price, parts and labour terms, and any additional work that might become necessary. If the recommendation is replacement rather than repair, ask why. An expensive diagnosis deserves enough explanation to be checked by another qualified person.

Record previous repairs and recurring symptoms. A repeated fault may call for a review of the installation or application as well as the failed part. A brand reputation or a general lifespan range cannot tell you the remaining life of your own unit.

Compare outcomes, not only today’s bill

A repair can preserve useful equipment and defer a large purchase. Replacement can address an unsuitable unit or form part of a broader system change, but the full installation cost and uncertainties belong in the comparison. Do not treat claimed future fuel savings as guaranteed cash in hand.

Ask whether duct, vent, control or envelope work is needed under either option. If the replacement leaves the original comfort problem unexplained, a more expensive box may not deliver the hoped-for improvement. A second opinion is useful when the diagnosis or proposed intervention remains unclear.

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Sources & verification

Research snapshot: 11 October 2026. Confirm the current complete model, Canadian supply and warranty before purchase.