Start with the age of the furnace
Most gas furnaces installed in the Edmonton area last 15–20 years. Under 10 years old, repair is almost always the right call — the equipment has plenty of life left and parts are easy to source. Past 15 years, every repair has to be weighed against the fact that the rest of the furnace is aging at the same rate.
Age alone doesn't condemn a furnace. A clean, well-maintained 14-year-old furnace with a single failed igniter is a repair. A neglected 14-year-old furnace with a failing inducer, a noisy blower, and rust in the heat exchanger area is a different conversation.
The 50% rule (and where it breaks down)
A common rule of thumb: if a single repair costs more than about 50% of a replacement, replacement usually wins — especially on older equipment. It's a useful gut check, but it's not the whole picture.
What matters more is the combination: a high repair cost on an old furnace that's also losing efficiency and out of warranty. One of those factors is a repair. Three of them stacked together is when replacement becomes the smarter spend.
The one part that changes everything: the heat exchanger
A cracked or failed heat exchanger is the clearest replace signal. It's one of the most expensive components, it's a combustion-safety issue, and on an older furnace it rarely makes sense to put that kind of money into aging equipment. If we find heat-exchanger damage, we'll show you and explain exactly why we're flagging it — we don't ask you to take it on faith.
Don't ignore efficiency and comfort
An older mid-efficiency furnace can run far below the 95–98% AFUE of a modern condensing unit. Over an Edmonton heating season, that gap shows up on your gas bill. If your furnace is old, inefficient, and now needs a real repair, the replacement can start paying for part of itself in operating cost — and a properly sized new system usually heats more evenly, too.
How we make the call with you
We diagnose first, every time. You get the actual fault, the readings behind it, the repair cost in writing, and — if replacement is genuinely worth considering — a clear side-by-side so you can decide. No scare tactics, no pressure to replace something that has years left in it.