Components
Heat exchanger
The metal chamber inside a furnace where combustion gases transfer heat to indoor air — without mixing.
The heat exchanger keeps combustion gases (carbon monoxide, water vapour) separate from the air you breathe. Hot exhaust passes through one side; your indoor air passes around the outside; heat transfers across the metal wall; the exhaust gets vented outside.
When the heat exchanger cracks (from thermal cycling stress over 15–20 years), CO can leak into your supply air. This is the single most dangerous failure mode in a residential furnace.
We inspect the heat exchanger with a borescope on every furnace tune-up. If we find a crack, we tell you and we don't run the unit. Replacement is usually simpler than repair on older units.
More in Components
Open 24/7
Want plain-English advice for your home? Call.
Most GTA calls get same-day service. Call, text, or request a fixed quote — we'll come back with a real ETA.
Mississauga, ON · Greater Toronto Area and up to 2 hours out — London, Kitchener, Barrie, Kingston, Niagara.