Description Of Functions - Ariston Heat pump water heater User Manual

The heat pump owes its name to the fact that it
can transfer heat from a lower temperature source
to a higher temperature source, thus reversing the
natural flow of heat which, as we can all experience,
moves from a higher to a lower temperature source.
The advantage of using a heat pump is that it can
supply more energy (in the form of heat) than that
required for its operation (electrical energy). The
heat pump is capable of extracting heat from heat
sources present in the environment, in a free-of-
charge way, given their nature and availability.
In the case of the NUOS water heater, heat is extracted from the stuffy internal air that must be renewed and thus
contributes to increasing water heating efficiency. Several different configurations can be selected for using ambient
air, making the appliance highly versatile in relation to different installation conditions.
The NUOS water heater is designed and manufactured in compliance with the specifications on the energy performance
of buildings and allows for a more rational use of energy and enhances savings on energy bills. The capacity to extract
heat from free energy sources reduces the environmental impact of emissions into the atmosphere compared to
alternative systems used in producing domestic hot water.
With reference to the average annual consumption of domestic hot water for a household of four, the table below
indicates the approximate emissions of carbon dioxide compared to alternative systems:
Type of appliance / technology
NUOS heat pum water
heater
Water heater with heating element
Methane gas fired water heater

2.2 Description of functions

As previously mentioned, the "energetic capacity" of a heat pump is that of transferring heat by extracting it from a
free source (ambient air in this case) with a lower temperature compared to that of the substance to be heated (i.e.
the water contained in the water heater's tank). Electric energy is thus needed to power the compressor and cause
the refrigerating fluid inside the refrigerating circuit to change state, so thermal energy can be transferred.
The refrigerating fluid moves through a closed circuit inside which the fluid changes to the liquid or gas state in relation
to its temperature and pressure. The circuit (Fig. 2) mainly comprises the following:
Annual CO (in kg) emissions
2
per year for each family
450
1.400
620
GENERAL INFORMATION
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