The following glossary is based on information provided by topten.eu and taken from additional sources such as technical standards and legislative documents.

Heat pumps

COP – Coefficient of Performance: the ratio of heat output delivered to the heating circuit against the electrical input. An example: for a heating capacity (output) of 10 kW (e.g. 1st test condition) and an electrical power input of 2 kW, the COP value is 5 (10 kW / 2 kW = 5). This means that the electrical power used is transformed in 5 times more usable heat output.

Heat output: the useful heat output delivered by the heat pump under certain test conditions, in kW.

• W = water inlet temperature / heater outlet water temperature in °C
• A = air inlet temperature in °C
• B = brine inlet temperature in °C

Example: B0/W35 means the brine-to-water heat pump is operated with 0°C brine source temperature and 35°C water supply temperature

Heat pump type	1st test conditions	2nd test conditions
Brine/water heat pump	B0/W35	B0/W55
Water/water heat pump	W10/W35	W10/W55
Air/water heat pump	A2/W35	A-7/W35

Heat pump type:

• BW = brine / ground source to water heat pump
• AW = air to water heat pump
• WW = water / ground water to water heat pump

SCOP – Seasonal Coefficient of Performance: According to standard EN 14825 the SCOP describes the heat pump’s average annual efficiency performance, and reflects themperatures and resulting COPs of different seasons. SCOP is therefore an expression for how efficient a specific heat pump will be for a given heating demand profile