Operating Principle - Panasonic Aquarea B1 Planning And Installation Manual

Product Description
4 Product Description
4.1

Operating Principle

Pleasant indoor temperatures just above 20 °C are needed to ensure living comfort. This tem-
perature does not differ much from the outside temperature over most of the year.
In contrast to heating with burners, which generate temperatures of several hundred degrees
as part of the combustion process, a heat pump generates only the temperature that is needed
at the moment. The Aquarea air-to-water heat pump uses the thermal energy contained in the
ambient air to heat the building and to provide hot water. In other words, the system uses freely
available ambient heat. Power is only needed to supply the compressor, the electronics and the
pumps, and in extremely low outside temperatures, to operate the E-heating element.
Functioning principle of an air-to-water heat pump
1
1 Thermal energy contained in the ambient air
(evaporator)
2 Power
16
Aquarea air-to-water heat pumps - Planning and installation manual - 01/2018
2
4
3
5
3 Useful heat (liquefier)
4 Compressor
5 Expansion valve
In a circulation process, ambient heat is brought to a higher temperature level. An environmen-
tally-compatible coolant passes through four steps:
● In the evaporator (1), the coolant boils and goes from the liquid phase to the gas-
eous phase. In this step, heat is extracted from the environment.
● In the compressor (4), the pressure of the gaseous coolant is sharply increased,
and the temperature also rises. This step takes place with supply of electrical ener-
gy (2).
● In the condenser (3), gaseous coolant condenses and transfers the heat of con-
densation to the water to be heated, while it also cools down at the same time.
● When passing through the expansion valve (5), the pressure of the fluid coolant
drops so abruptly that its temperature drops sharply and it can absorb ambient heat
again.
This circulation process runs continuously and can be controlled using the Inverter Plus technol-
ogy of the Aquarea heat pump in such a manner that the current heat requirement is covered.
By inverting the circulation process, it becomes a cooling machine. Aquarea heat pumps can
thus also be used for room cooling.
Coefficient of Performance and Performance Number
The COP (coefficient of performance) of a heat pump for the heating mode is defined as the
ratio of the emitted thermal output to the electrical power consumed and thus says something
about the efficiency of the heat pump at a given moment. The COP of heat pumps differs, de-
pending on the outside temperature and temperature of the generated heat. It is generally true
that the COP drops with increasing the temperature difference between the outside temperature
and the temperature of the useful heat. A comparison of the efficiency of various heat pumps is
only possible at the same temperature. COPs for air-to-water heat pumps are usually measured
and stated at the following temperatures for better comparability:
Outside temperature
A–15
A–7
A7
A2
(A stands for Air, W stands for Water)
Example
Coefficient of Performance = 4.74 (A7 / W35)
At an outside temperature of 7 °C, the air-to-water heat pump generates hot water at 35 °C with
a COP of 4.74. Thus, it is possible to generate 4.74 kilowatt hours of heat from one kilowatt hour
of power.
The performance number, which represents the ratio of the emitted heat to the consumed quan-
tity of power over a certain period, is more meaningful than the COP. The annual performance
number (JAZ) is the ratio of the generated heat to the needed quantity of power over the period
of one year. It is recorded by means of meters for power and amount of heat and takes all oper-
ating states of the heat pump systems into consideration.
Aquarea air-to-water heat pumps - Planning and installation manual - 01/2018
Product Description
Useful heat
W35
W35
W35
W55
17