Within the field of HVAC, there are lots of different specialties, and deciding whether to focus on residential or commercial HVAC is one part of the career path to consider. Residential HVAC: Technicians spend most of their time doing house calls to help homeowners or renters install, repair, replace, diagnose or troubleshoot their HVAC systems. You might work alone or in a small team, and the demand may change depending on the time of year, such as right before it gets very hot or very cold. Residential work is more customer-facing, so you could be interacting with different people every day. Commercial HVAC: This involves doing bigger project work for businesses or other types of large-scale properties, such as schools or restaurants. These projects may last longer, and you will likely work as a part of a team to approach more complex HVAC challenges such as construction or renovation. Commercial work is less customer-facing, and more project-based, so you could enjoy more time and energy focusing on high-level systems thinking.