What type of furnace would be used on a home when the supply duct is run in the crawl space and the furnace is installed on the main floor?

In a scenario where the supply duct is run in the crawl space and the furnace is installed on the main floor, a counterflow furnace is the most suitable choice. This type of furnace is designed to have the air intake at the bottom and the air supply at the top. By using a counterflow configuration, warm air can rise effectively into the living space from a furnace installed in a basement or crawl space, promoting better airflow and efficient distribution of heated air throughout the home.

Counterflow furnaces facilitate this design by allowing the heated air to move upward naturally due to convection, effectively taking advantage of the furnace location. This design is particularly valuable in homes where ductwork runs through lower areas, as it allows for a straightforward installation that doesn't require elaborate duct systems to push air upward through complex routing.

Understanding the physical layout of the home and how the systems interact is crucial when selecting the right type of furnace. A larger awareness of furnace designs facilitates making informed decisions that enhance heating efficiency and comfort.