Editing Heat pump (section)

===Space heating and sometimes also cooling===
In HVAC applications, a heat pump is typically a [[vapor-compression refrigeration]] device that includes a [[reversing valve]] and optimized heat exchangers so that the direction of ''heat flow'' (thermal energy movement) may be reversed. The reversing valve switches the direction of refrigerant through the cycle and therefore the heat pump may deliver either heating or cooling to a building.

Because the two heat exchangers, the condenser and evaporator, must swap functions, they are optimized to perform adequately in both modes. Therefore, the [[SEER|Seasonal Energy Efficiency Rating]] (SEER in the US) or [[European seasonal energy efficiency ratio]] of a reversible heat pump is typically slightly less than those of two separately optimized machines. For equipment to receive the [[Energy Star|US Energy Star]] rating, it must have a rating of at least 14 SEER. Pumps with ratings of 18 SEER or above are considered highly efficient. The highest efficiency heat pumps manufactured are up to 24 SEER.<ref>{{Cite web |title=Heat Pump Efficiency {{!}} Heat Pump SEER Ratings |url=https://www.carrier.com/residential/en/us/products/heat-pumps/heat-pump-efficiency/ |access-date=2023-01-14 |website=Carrier |language=en |archive-date=2023-01-14 |archive-url=https://web.archive.org/web/20230114133418/https://www.carrier.com/residential/en/us/products/heat-pumps/heat-pump-efficiency/ |url-status=live }}</ref>

[[Heating seasonal performance factor]] (in the US) or [[Seasonal Performance Factor]] (in Europe) are ratings of heating performance. The SPF is Total heat output per annum / Total electricity consumed per annum in other words the average heating COP over the year.<ref>{{Cite web |date=2019-11-07 |title=COP and SPF for Heat Pumps Explained |url=https://greenbusinesswatch.co.uk/cop-vs-spf |access-date=2024-02-22 |website=Green Business Watch UK |language=en-GB}}</ref>

====Window mounted heat pump====
[[File:Window heat pump.webp|thumb|Saddle-style window mounted heat pump 3D sketch]]
Window mounted heat pumps run on standard 120v AC outlets and provide heating, cooling, and humidity control. They are more efficient with lower noise levels, condensation management, and a smaller footprint than [[Packaged terminal air conditioner|window mounted air conditioners]] that just do cooling.<ref>{{cite web |date=11 June 2024 |title=Why This Window Heat Pump is Genius – Undecided with Matt Ferrell |url=https://undecidedmf.com/why-this-window-heat-pump-is-genius/}}</ref>