HVAC Glossary

A unit of thermal energy commonly used to describe HVAC capacity.

A seasonal cooling-efficiency rating used for central air conditioners and heat pumps.

A cooling-efficiency rating measured at a specified full-load test condition.

A seasonal heating-efficiency rating for air-source heat pumps.

An HVAC capacity unit equal to 12,000 BTU per hour of heat-transfer rate.

A dimensionless ratio comparing useful heating or cooling delivered with the work supplied to the system.

A specific combination of HVAC components evaluated together as one system.

A unique identifier used by AHRI for a certified HVAC equipment combination or product record.

Heating and cooling equipment that uses a refrigeration cycle to move heat between locations.

A compressor drive system that can vary compressor speed and capacity instead of operating only fully on or fully off.