What is Heating?

How It Works

  1. A heat exchanger contains refrigerant, which is colder than the outside air. As the air passes the exchanger, the refrigerant absorbs the latent heat from the outside air and evaporates.
  1. The vapour passes into the compressor and is compressed, increasing its pressure and temperature, effectively concentrating the heat.
  1. Hot vapour is condensed in the second heat exchanger where heat is rejected and the vapour condenses back into a liquid. The rejected heat passes into the central heating and hot water system, ready for use in the home.
  1. The liquid refrigerant passes back through an expansion valve, ready to start the cycle again.


Heat pumps are inherently clean and reliable, and traditionally use water to water or air to air technology. The Altherma air to water system, however, represents the best of both technologies, combining

  • the accessibility of air as the heat source;
  • low investment cost (no high cost drilling or extensive excavation work is required nor the construction of a chimney, consequently, the system is ideally suited for inner city application or where space is limited);
  • emission free operation;
  • easy installation and maintenance, with the comfort of using a water based heating system.


Heat sources for low temperature heating systems include conventional fossil fuel boilers and electricity. Altherma as an alternative is a far more efficient solution. More than 2/3 of the energy used by Altherma over the year is freely available in the air. The system can operate down to -20°C (including backup heater). As a result, Altherma can generate all the heat necessary to warm a house comfortably. All heat pumps require electrical input in order to upgrade the low temperature.


The Altherma system features an outdoor and indoor unit; both are compact. The outdoor unit can be located discreetly outside new and existing residential buildings. The indoor unit can be installed in any convenient space, removing the need for a dedicated technical room.


In addition to the basic comfort requirements of providing heat, Altherma can deliver even more. The system is designed to supply your sanitary hot water needs all year round and can be selected with a cooling option for the hot summer months, thus satisfying your desires for all year-round comfort.

Altherma can be configured in three ways – monoenergetic, monovalent and bivalent – to optimise the balance between investment and running costs, and to extend the types of projects for which Altherma can be used. Professional Daikin installers will provide details on how each of these versions can be applied to any particular building. In addition to these three configurations, Altherma can also be combined with alternative renewable heat sources such as solar panels for domestic hot water heating.