A heat pump water heater is a type of water heater that uses heat pump technology to heat water. The heat pump water heater is more environmentally friendly because it uses less energy and produces fewer emissions. This type of water heater is also more versatile than traditional water heaters because it can be used to heat water for a variety of purposes, including domestic hot water and swimming pool heating. Additionally, heat pump water heaters are also very reliable and have a long life expectancy.