How Do Water Heater Heat Pumps Work?

Heat pump water heaters are a cost-effective way to meet your domestic hot water needs.

This water heater is an example of an air source heat pump. It extracts ambient heat from the surrounding air and circulates it inside the heat pump to raise the temperature. As it moves heat rather than producing it, a heat pump water heater is two to three times more efficient than an electric water heater.

The efficiency of a heat pump water heater is determined by the system’s quality, the installation’s quality, your climate’s average temperatures, and the compressor unit’s location.

Heat pump water heaters come in two varieties:

  • Split systems are similar to air conditioning systems in that the water tank and compressor are distinct
  • Both the compressor and the water tank are housed in the same unit. Typically, the entire system is installed outside
How Do Water Heater Heat Pumps Work

How Do Water Heater Heat Pumps Work?

Heat pump water heaters use electricity to draw ambient air and circulate it through the pump, raising the temperature, which is then dumped into the water tank and used to heat domestic hot water.

A heat pump water heater functions similarly to a refrigerator, but in reverse. A heat pump water heater pulls in ambient air from the outside and warms it up inside, rather than dragging hot air from the inside and dumping it outside.

As it does not use electricity to produce heat like an electric water heater, a heat pump water heater is more efficient than an electric water heater.

  • A fan draws in the surrounding air
  • The air passes through an evaporator coil filled with a refrigerant, turning it into a vapour
  • A compressor compresses the vapor, increasing its temperature
  • The vapor moves to a coil placed in a tank filled with water, heating the upper part of the tank
  • Cold water enters the tank at the bottom and cools the vapor, that then returns to the evaporator in liquid form

Instead, it absorbs heat from the outside and then circulates it using electricity, eventually transferring the heat to the water. This type of heat pump generates condensation, so you’ll need to install a condensate drain.

How About Cold Climates?

Heat pump water heaters take in the surrounding air and heat it up inside the system. The heat pump will have to work harder to heat the surrounding air if it is cold. Therefore, making them less efficient in cold climates.

They thrive in climates with year-round temperatures ranging from 4 to 32 degrees.

Furthermore, since the cold air is expelled while the hot air is kept inside the heater, heat pump water heaters tend to cool the space around them. This means you’d have a heat pump water heater in the winter to help cool your space even more.

Installation of a Water Heater Heat Pump

Many factors go into the proper installation of a heat pump water heater. The layout of your house, the environment, and local building codes are just a few of these considerations. As a result, it is recommended that you hire a qualified plumbing and heating contractor to properly install your heat pump.

Heat pump water heaters need a minimum of 28.3 cubic metres of air space around the unit.

Installation of a heat pump water heater usually takes between 7-8 hours.If a concrete pad is required then this will need to be poured 24hrs before installing the heat pump.

Are Water Heater Heat Pumps a Good Investment?

Water heaters that are well-designed and installed use less energy than standard electric cylinders, making them a good investment for your home. Heat pump water heaters can be used in areas where solar water heaters fail because they don’t need a lot of sun exposure, such as the south side of hills.

Over time, heat pumps are expected to expand significantly in New Zealand. Heat pumps take a little longer to install, but they are definitely considered a good investment in the long run, both environmentally and economically.