The most common type of central heating system used in Canadian homes is the forced-air system with a furnace as its heat source, and ducts and registers for distribution. The furnace delivers heated air blown by a fan through a network of ducts and the heat is distributed through the home through registers in the floors of each room. Because the fan is literally forcing air into each room in the house, this type of system does not depend on natural convection to distribute heated air evenly throughout your house. Forced-air systems come in a wide range of capacities. The heating elements, circulation fan, air filter, and control devices are contained in a compact cabinet.
To accommodate different types of houses, there are three main furnace designs for use with forced-air systems. The designs are named according to the way air travels through the system:
• Upflow furnaces are recommended for basement floor locations.
• Horizontal flow furnaces are particularly suited for crawl space installations
• Downflow furnaces are recommended for installations in mobile homes or on the main floor of houses on concrete slabs.
Advantages of Forced Air Systems (Furnaces):
- ability to provide heat quickly
- can be used to filter and humidify household air
- can provide ventilation and central air conditioning
- can be used year-round for continuous air circulation throughout the house, while efficiently balancing the distribution of heat.