Installation manual

6
What are the Benefits of a Heat Pump?
The fact that a large percentage of our energy supply is produced
from fossil fuels poses serious consequences for our
environment. Large quantities of pollutants such as sulphur and
nitrogen oxide are released during combustion.
Domestic space heating with fossil fuels contributes significantly
to pollutant emissions because extensive emission control
measures, such as those used in modern power plants, cannot
be carried out. Since our oil and gas reserves are limited, basing
such a large percentage of our energy supply on fossil fuel
sources also presents a serious problem.
The way electrical energy is generated will change in the future
to favour more renewable or newly developed generation
methods. You, too, can be a part of this development because
electricity as the energy of the future is the operating energy of
heat pumps.
What does a heat pump do?
A heat pump is a type of “transport device” that raises the
temperature level of the heat that is freely available in the
environment.
How does a heat pump convert low temperature
heat into higher temperature heat?
It extracts stored solar heat from the environment – ground,
water (e.g. ground water) and air (e.g. outside air) – and transfers
this, along with the operating energy, in the form of heat to the
heating and hot water system.
Heat cannot transfer from a cold body to a warm body on its own.
Rather, it flows from a body with a higher temperature to a body
with a lower temperature (Second Law of Thermodynamics). For
this reason, the heat pump must raise the temperature of the
thermal energy extracted from the environment using high-grade
energy - e.g. electricity for the drive motor - to a level suitable for
heating and domestic hot water preparation.
Heat pumps work like a refrigerator – in other words, the same
technology is applied but the function is reversed. It extracts heat
from a cold environment which can then be used for heating and
domestic hot water preparation.
Glossary
Defrosting
Regular routine for removing frost and ice from evaporators on
air-to-water heat pumps by applying heat. Air-to-water heat
pumps with reversal of the direction of circulation feature the
rapid and energy efficient defrosting properties required.
Bivalent-parallel operation
The bivalent operating mode (today this is normally bivalent-
parallel operation) functions with two heat generators (two
sources of energy), i.e. the heat pump covers the heating
requirements up to a determined temperature limit (as a rule
-5 °C) and is then backed up by a second energy source in
parallel.
Bivalent-renewable operating mode
The bivalent-renewable operating mode makes it possible to
incorporate renewable heat sources such as wood or thermal
solar energy. Should renewable energy sources be available,
then heat pump is blocked and the current heating, hot water or
swimming pool needs are met by the renewable cylinder.
Carnot factor
The ideal reference cycle for all thermodynamic cycles is the so-
called Carnot cycle. This (theoretical) model cycle gives
maximum efficiency and - in comparison to a heat pump - the
theoretically greatest possible COP. The Carnot factor is based
solely on the temperature difference between the warm side and
the cold side.
D-A-CH seal of approval
Certificate for heat pumps in Germany, Austria and Switzerland
which fulfil specific technical requirements, have a 2-year
warranty, ensure the availability of spare parts for up to 10 years
and whose manufacturers offer a comprehensive customer
service network. The seal of approval also certifies that a line of
heat pumps has been manufactured as a series.
Utility company shut-off times
Local utility companies offer special tariffs for heat pumps
providing the power supply can be shut off by the utility company
at certain times of day. The power supply can, for example, be
interrupted for 3 X 2 hours within a 24-hour period. This means
that the daily heat output (quantity of heat produced daily) must
be produced within the period of time in which electrical energy is
available.
Expansion valve
Heat pump component between the liquefier and the evaporator
for reducing the condensation pressure to coincide with the
respective evaporation pressure determined by the evaporation
temperature. The expansion valve also controls the quantity of
refrigerant to be injected in relation to the respective evaporator
load.
Limit temperature / bivalence point
The outside temperature at which the 2nd heat generator is
additionally connected in mono energy (electric heating element)
and bivalent-parallel operation (e.g. boiler), and both modes of
operation jointly provide the house with heat.
Annual performance factor
The annual performance factor is defined as the ratio of the
quantity of electrical energy supplied in one year to the amount of
thermal energy extracted by the heat pump system. It is based
on a particular heating system taking the respective design of
that system into consideration (temperature level and
temperature difference) and is not the same as the coefficient of
performance.
Annual effort figure
The annual effort figure is exactly the opposite of the
performance factor. The annual effort figure indicates what input
(e.g. electrical energy) is required to achieve a defined benefit
(e.g. heating energy). The annual effort figure also includes the
energy for the auxiliary drives. The VDI Guideline VDI 4650 is
used to calculate the annual effort figure.