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Forced-air furnaces

A forced-air natural gas furnace uses ductwork and vents to distribute warm air throughout the house. The primary components of this system include an air filter, blower, heat exchanger and various controls. A thermostat is used to control the temperature in the house.


Comfortable, evenly balanced warmth - forced-air heating usually brings in fresh air from the outside for ventilation, creating a healthier environment than electrical baseboard installations, which have no ventilation component.

Improved air quality - the furnace’s air filter reduces airborne pollutants such as dust and improves indoor air quality. The sealed combustion in high-efficiency models also protects indoor air quality by isolating the burner and flue from the home.

Furnace efficiency

Look at the furnace’s Annual Fuel Utilization Efficiency (AFUE), a rating system used to estimate the equipment’s efficiency. The higher the rating, the more efficient the furnace is.

ENERGY STAR® certified systems

If your furnace was installed before 1990, it’s likely a lower-efficiency model, averaging only between 60 and 70 per cent AFUE. Consider upgrading it to ENERGY STAR®. ENERGY STAR certified natural gas furnaces in Canada are rated between 95 to 99 per cent AFUE. This means when the furnace is installed to a quality standard, approximately only between five and one per cent of the heat is lost.

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