What are the two main types of heating systems in HVAC?

The identification of forced air systems and radiant heating systems as the two main types of heating systems in HVAC is based on their fundamental methods of heat transfer and distribution.

Forced air systems function by heating air and then distributing it throughout a space via ductwork and vents. This method is widely used due to its efficiency in quickly raising the ambient temperature of a room and can integrate air conditioning for complete climate control.

Radiant heating systems, on the other hand, operate by heating surfaces, such as floors or walls, which then radiate heat into the room. This approach provides a more even temperature distribution and enhanced comfort, as it heats objects and people directly instead of just heating the air.

Both of these systems are commonly utilized in residential and commercial applications, making them significant within the HVAC field. Other choices may describe heating systems, but they do not represent the main categories of heating methods as effectively as forced air and radiant systems do. Thus, option B encompasses the most recognized and prevalent types of heating systems in the HVAC industry.