Specification glossary

Mini-split terms without sales fog

Definitions for the acronyms and terms used in model spec tables, comparisons, sizing tools, and buyer guides.

AHRI

Air-Conditioning, Heating, and Refrigeration Institute; its directory is used to look up certified equipment performance. Source: AHRI Directory of Certified Product Performance

British thermal units per hour, a rate used to state heating or cooling capacity. Source: EPA ENERGY STAR room air conditioner sizing guidance

Cold-climate air-source heat pump as used by the NEEP specification and product list. Source: NEEP cold-climate air-source heat-pump specification and product list

Coefficient of performance, a ratio used to describe heat-pump output relative to energy input at stated conditions. Source: U.S. Department of Energy heat pump guide

Cooling efficiency at a defined test condition under current ENERGY STAR heat-pump criteria. Source: EPA ENERGY STAR heat pump key product criteria

Shopper shorthand for an indoor unit serving a conditioned area in a ductless system. Source: EPA ENERGY STAR ductless heating and cooling

Heating Seasonal Performance Factor 2, a seasonal heating-efficiency metric. Source: EPA ENERGY STAR heat pump key product criteria

The part of a ductless system that delivers conditioned air inside the served area. Source: EPA ENERGY STAR ductless heating and cooling

A variable-speed drive approach used by many heat pumps to modulate operation rather than only switching fully on or off. Source: U.S. Department of Energy heat pump guide

The manufacturer-specified refrigerant piping assembly connecting indoor and outdoor equipment. Source: MRCOOL installation and owner manual

The ACCA residential heating and cooling load-calculation standard. Source: ACCA Manual J residential load calculation

Minimum circuit ampacity, an equipment electrical value that belongs in the electrician and code review for the exact model. Source: MRCOOL installation and owner manual Source: NFPA 70 National Electrical Code

Maximum overcurrent protection, an equipment electrical limit that must be read from exact model documentation and applied under local code. Source: MRCOOL installation and owner manual Source: NFPA 70 National Electrical Code

The exterior equipment connected to one or more indoor units in a ductless system. Source: EPA ENERGY STAR ductless heating and cooling

Seasonal Energy Efficiency Ratio 2, a seasonal cooling-efficiency metric. Source: EPA ENERGY STAR heat pump key product criteria

A ductless arrangement serving one conditioned area with one indoor-unit relationship to an outdoor system. Source: EPA ENERGY STAR ductless heating and cooling

A ductless arrangement connecting multiple indoor areas to an outdoor system; verify the exact rated combination. Source: EPA ENERGY STAR ductless heating and cooling Source: AHRI Directory of Certified Product Performance