In HVAC, how is the output of a heating system commonly measured?

The output of a heating system is commonly measured in British Thermal Units (BTUs). A BTU is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. This unit is particularly relevant in HVAC because it provides a standardized measure of heat output and is widely used in the industry to describe the capacity of heating equipment.

When assessing the heating capacity of systems such as furnaces, heat pumps, or boilers, professionals will often refer to the BTU rating. This allows for a clear comparison of different systems and aids in selecting equipment that meets the heating needs of a specific space.

Other units of measurement, such as watts and horsepower, may apply in broader contexts (like electrical output or motor capability), but they do not specifically reflect the thermal energy that heating systems deliver in the context of HVAC. Gallons might refer to liquid volume but is not an appropriate measure of heat output, especially in this field. Understanding BTUs helps in ensuring that the heating system chosen can adequately and efficiently handle the demands of the environment being serviced.