How Mitsubishi Electric Ecodan Works
The technology inside an air source
heat pump is similar to any domestic refrigerator, which
uses a vapour compression cycle. The main components in
the heat pump are the compressor, the expansion valve
and two heat exchangers.
Overview
Heat pumps move heat in the air into the home to
provide a total solution for Domestic Hot Water (DHW)
and all heating needs. Because heat pumps simply move
energy, rather than creating it by burning fossil fuels,
they are very efficient. For every 3KW of heat moved
into the house only 1KW of electricity is consumed. This
gives a perceived efficiency of 300% sometimes stated as
a Co-efficient Of Performance (COP) of 3:1.
Collecting the Heat
Heat collection is achieved by using a fan to force
air, over a heat exchanger (simply a copper coil filled
with refrigerant) to extract heat fro the air.
The Evaporator
The purpose of the Evaporator is to take heat
obtained by the heat exchanger and boil a refrigerant
(which boils at approximately -10°C), the act of boiling
turns the refrigerant into a vapour which is then moved
into the Compressor.
The Compressor
The Compressor does exactly what its name suggests;
the vapour is compressed in volume and as its volume
reduces its temperature increases. Temperatures of
between 75°C and 125°C are achievable and the gas is
then fed through a heat exchanger.
Condenser/heat exchanger
Forcing the hot gas across the cold water from the
central heating system condenses the refrigerant turning
it back into a liquid. As it condenses its heat is
passed into the heat exchanger which supplies the DHW
and central heating system.
The Expansion Valve
To complete the closed circuit of the heat pump the
only thing which needs to be done is reduce the pressure
of the condensed liquid and this is done via an
Expansion Valve
