Residential HVAC Installation Practice Exam 2025 - Free HVAC Practice Questions and Study Guide

The most common HVAC system type found in older homes is central air conditioning with a forced-air furnace. This system has been widely used for many decades and involves a furnace that utilizes air as the medium for heating, while central air conditioning components are integrated into the same ductwork system for cooling.

The forced-air furnace heats air, which is then distributed throughout the home using ductwork, making it an efficient option for heating in older residences. Many homes from the mid-20th century were constructed with this configuration because it was a standard building practice at the time, resulting in a significant number of homes still utilizing this HVAC system today.

In contrast, mini-split systems, while becoming more popular, are not typically found in older homes due to their more recent development and installation practices. Similarly, geothermal heating and cooling, known for its energy efficiency and environmental benefits, is more commonly installed in new constructions rather than existing older homes. Variable refrigerant flow systems are advanced technologies typically used in modern applications, especially in commercial settings, and are not a standard choice for the residential setups of older properties.