Heat Pump Water Heaters (HPWH) for the general public are traditionally considered to be mono-bloc air source heat pump used in individual dwellings or apartments. However there is a great number of other Heat Pumping Technologies for generating sanitary hot water.

HPWH for individual dwellings or apartments
A variety of HPWH can be categorized here:
- Mono-bloc electric air source HPWH;
- Split electric air source HPWH;
- Sorption gas driven air source HPWH;
- Booster HPWH, with low temperature water as heat source;
- Fresh water HPWH;
- Solar supported air source HPWH.
The choice is broad where in Asia the ECO-Cute is dominating the market while in a country like Netherlands water heating is more than often combined with space heating.
Heat pumps in collective systems normally feed a distribution system and need for DHW to generate temperatures of at least 65°C and higher, which a number of technologies can achieve, including:
- Cascade systems Heat Pumps;
- Enhanced Vapour Injection (EVI);
- Heat Pumps with specific refrigerants such as CO2;
- Gas driven heat pumps.
Alternative and innovative systems are applied, like Fresh Water Systems, PVT-combinations and anergy sources.
