Glossary Of Terms - Grant Aerona HPAW65 Installation & User's Instructions

16 Glossary of Terms

Efficiency
The word "efficiency" is defined as the
ratio of useful heat output to energy
input. For example, if we use 1 kW of
energy to produce 500W of heat it is
deemed to be 50% efficient.
COP
The COP or 'Coefficient of
Performance' is found by dividing the
useful heat output by the energy input.
For example; a heat pump that
produces 4 kW of heat for 1 kW of
input power has a COP of 4.
Source
This is wherever the heat is being
extracted from e.g. the outside air or
ground.
Emitters
A term used to describe radiators or
underfloor heating. This is the
component that 'emits' the heat into
the building.
Refrigerant
The working fluid within the heat pump.
It evaporates in one part and
condenses in another. By doing so,
heat is transferred from cold to hot.
This fluid is sealed in and will not
degrade within the life of the heat
pump. Refrigerant handling should only
be carried out by persons qualified to
do so.
Heat Exchanger
A component that allows the
transference of heat from one circuit to
another without the two circuits mixing.
Two heat exchangers are housed within
the heat pump, one for the hot side (the
condenser which transfers the heat to
the heating circuit) and one for the cold
side (the evaporator).
Buffer Tank
This is simply a large water cylinder that
can be used to improve the efficiency
and durability of a system. In fact, it
reduces the number of stop/starts the
compressor makes.
Heat Pump Rating
A heat pump is given a kW heat output
rating. This value will vary depending on
the working temperatures. The electrical
power input will be typically between a
half and a quarter of the heat output.
Monovalent
A monovalent system is one where all
of the energy required for the heat load
of the building is available from the heat
pump.
Bivalent
Bivalent systems are those which
require an additional source to meet the
buildings heat load.
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