Glossary

Air Source Heat Pump

Capture of heat in the air by means of an external unit (wall-hung mounted or floor standing).

Horizontal ground collector

Heat is taken from the ground via a network of coils of polyethylene-coated copper pipes ( Direct evaporation system) or of crosslinked polyethylene XLPE pipes (brine to water systems) inside which the refrigerant ( Direct evaporation system) or the brine ( Brine to water systems) circulates. This horizontal ground collector is buried 60 to 80 cm underground, over an area of about 100% to 120% of the surface to be heated ( Direct evaporation system) or 150% to 200% of the surface to be heated ( Brine to water system) depending on the region.

Vertical collector, or geothermal probe

Geothermal probes are filled with brine ( glycol + water), which circulates inside a closed circuit and collects energy from between 50 and 100 metres underground. The drilling phase involves making a double U-shaped loop. The number and depth of these loops will differ according to the heating capacity required.

Groundwater collector

The groundwater collector is a good solution in cases where the land concerned has sufficient water underground at a depth of 10 to 20 m. Heat is taken directly from water tables underground, whose temperature is constant throughout the year. (between 10 and 12°C). This means that the heat pump will have a high efficiency.

Air collector

The air collector takes calories from the outside air, and transferring them to a central heating network . It can work in temperatures as low as -10°C

Coefficient of performance (COP)

The COP is the Coefficient of Performance. It is the ratio of the thermal energy given out for heating to the electrical energy consumed in running the heat pump. For 1 kWh of electrical energy consumed by the compressor, a heat pump with a COP of 4 provides the equivalent of 4 kWh of heat.

Compressor

Main component of the heat pump in which refrigerant is compressed, raising its temperature.

Heat emitter

Device in a room of a dwelling that transmits heat from the heating system. Radiators, underfloor heating and fan convectors are all types of heat emitter.

Brine or Glycol water

Water with an antifreeze solution ( Glycol) added which circulates in the collectors buried outside the dwelling in order to capture heat energy.

Evaporator

Heat exchanger enabling the recovery of energy from the collector.

Refrigerant

Fluid contained in the heat pump which enables heat transfers during its changes of state (between liquid and gas). The operation of thermodynamic machines (such as refrigerators and heat pumps) is based on the ability of refrigerants to vaporise at negative temperatures and condense at room temperature.

Geothermal power

Capture of heat energy stored in the earth at shallow depths using a circuit of external collectors buried horizontally or a vertical geothermal probe. This source of heat is constantly renewed by the sun, the rain and the effects of the wind.
Low-temperature underfloor heating Heat emitter composed of tubes through which a liquid flows, giving out warmth into the rooms to be heated. Underfloor heating provides an even heat throughout the house. There are numerous benefits: the heat is well distributed between the floor and the ceiling, the air is healthy as it is never dried out, the floors are never cold in winter, and the rooms of your house are not cluttered by radiators. Low-temperature underfloor heating is properly sized so that its surface temperature remains moderate (around 23°C). In the case of the cooling option, the underfloor pipes network may also contribute to cooling the home, becoming an underfloor cooling. Hygrometry level has to be controlled.

Heat Pump

A heat pump is essentially a refrigerator in reverse: the refrigerator draws heat from its inside compartment and sends it outside to lower the temperature of the food. A heat pump, on the other hand, takes the heat provided by the outside environment (the air, water, or the earth beneath your garden) and makes use of it by raising its temperature and transferring it into the home via a distribution circuit (e.g. underfloor heating, network of existing radiators), which in turn provides a healthy, gentle and even heat, thanks to a precise and flexible adjustment system. The heat pump therefore uses a form of energy that is natural, inexhaustible, clean and economical: each kilowatt consumed to operate the heat pump gives 3 to 5 kW of useable heat for your home in return.

Air cooling

Air cooling is a moderate form of refrigeration which reduces the overall temperature in a dwelling by a few degrees. Reversible heat pumps are fitted with a device that reverses the direction of refrigerant flow, so that heat energy can be transferred from the house to be discharged outside.

Geothermal probe

Heat exchanger composed of polyethylene tubes that is inserted vertically into a loop drilled several tens of metres into the ground. The probe is then sealed in place with a special cement designed for this purpose. An antifreeze solution ( glycol + water) circulates inside the probe and captures heat from the ground beneath.

Fan convector. Fan coil

Emitter of hot or cold air that is connected to either a circuit of either heated or cooled water or an additional circuit of refrigerant provided by the heat pump. It filters and distributes air into the rooms of the house using fans.