System Types

The refrigerant changes to a liquid form when it is compressed through a 'condenser' coil - at this point it releases its heat energy into the hot water tank

The refrigerant passes through an expansion valve and expands to be come a gas (like the aerosol spray can)

The refrigerant absorbs the heat from the air around it as it is pumped through 'evaporator' coils outside the house

The compressor then pumps the refrigerant round again and again and the cycle continues

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Because the system only uses electrical energy to pump the gas and transfer the heat, the system is VERY efficient. So, for every $1 of electricity needed to run the compressor pump, the equivalent of about $3 of heat energy is transferred. This delivers much better efficiency compared to other water heating options. The efficiency can be between 2 and 4 times as good, depending on where you live, the outside air temperature and other conditions.

Generally, HPWH systems work well in areas with average air temperatures above about 5 Degrees C, but most will still operate efficiently to as low as -10 Degrees C.

Since the 1990's, all of the CFC refrigerants which were extremely harmful to the Ozone layer have been discontinued in favour of the more environmentally friendly products used today.

There are different types of Heat pump water heaters available. In some HPWH systems the hot water cylinder is split from the heat exchanger whereas others are all in-one. Heat exchange units are generally located outdoors and may produce some background noise.

check with your Local Authority regarding the noise limit in your area.