Illinois Home Inspector Practice Exam

Which of the following is not a forced air furnace configuration?

1. Horizontal

2. Vertical

3. Downflow

4. Upflow

The correct answer is: Vertical

In the context of forced air furnace configurations, the vertical, downflow, and upflow designs are recognized setups that direct airflow to distribute heat throughout a space. The upflow configuration moves air vertically upward from the furnace into the ductwork and then into the rooms. Downflow furnaces operate similarly but direct the air downward, often used in settings where the furnace is located in an attic or upper space. Horizontal furnaces are laid out on their side and typically used in confined spaces, such as crawl spaces or attics, where there's limited vertical height. While there are configurations termed "downflow" and "upflow," the designation as vertical typically does not reference a common or standard configuration in the same way that the others do. Each recognized design serves specific architectural and functional needs. However, the vertical configuration is often less common and may not always be categorized distinctly as a standard furnace configuration compared to the others mentioned. Thus, the identification of "vertical" as not fitting within conventional forced air furnace configurations aligns with standard practices observed in the field.