Annual servicing is recommended for gas furnaces, ideally before the start of the heating season in September or October. Service includes burner cleaning, heat exchanger inspection, ignition check, blower motor cleaning, gas pressure adjustment and a full safety test for carbon-monoxide leaks.

High-efficiency gas furnaces typically last 15–20 years with annual maintenance. Vancouver's mild climate means lower run-times than colder Canadian cities, which extends life — but salt-air corrosion near the coast and high humidity can shorten it.

Common causes are a thermostat set to "on" instead of "auto", a tripped flame sensor, a clogged condensate drain shutting down a high-efficiency unit, low gas pressure, or a failed ignitor. Most are repairable in a single service visit.

A typical residential high-efficiency gas furnace in Metro Vancouver costs $4,500–$8,500 installed depending on size, brand and venting requirements. Variable-speed and modulating models are at the upper end.

In our experience servicing Vancouver homes since 1999, Carrier, Lennox, Bryant and York have produced the most reliable mid-to-high-efficiency furnaces with the best parts availability. Goodman and Rheem offer strong value at lower price points.