Heat pumps

A heat pump takes energy from the environment (Air, Water or Ground), converts it into heat and releases it at a higher temperature into a cold environment. Though it mainly provides heating to a home via an emitter (radiator, floor heating or fan convectors), it can also produce domestic hot water (DHW) or heat up a pool.

But a heat pump can also work in a reversible version. It is then used to cool the indoor environment, like an air conditioner.

Different heat pumps depending on the energy source

The 3 main families of heat pumps are:

1. Aerothermal [Air/Water; Air/Air] - The calories are taken from the Air (outdoor or extracted).
2. Geothermal [Ground/Ground; Ground/Water; Glycol water/Water; Glycol water/Glycol water] - the calories are taken from the Ground.

Ground/Ground or Ground/Water heat pumps use a liquid refrigerant to capture the energy from the ground with horizontal collectors only. Glycol water/Water or Glycol water/Glycol water heat pumps use Glycol water with horizontal or vertical collectors.

3. Aquathermal [Ground water/Water; Circuit water/Recycled air] - the calories are taken from Water (groundwater).

Once the heat is produced, a heat pump can release it in two different ways and heat the cold environment using several types of emitters:

• Heat pumps [Air/Air; Circuit water/Recycled air], use Air as heat transfer source in a fan convector, which forces warm air into the cold environment.
• Heat pumps [Air/Water ; Ground/Ground; Ground/Water; Glycol water/Water; Glycol water/Glycol water; Glycol water/Water], use Water as heat transfer source in water radiators, floor heating, ceiling heating or wall heating.

A heat pump can come as a single unit (“single-unit”), installed outdoors, in two units (“single-split” or “split”) or multiple units (“multi-split”), in which the condenser is placed inside the medium to be heated.

Heat pump to heat, cool or produce hot water

• A heat pump can be used to heat the pool water (pool heat pump) or a closed space in winter.
• It can also cool a hot environment during the summer (reversible heat pump) by drawing heat from inside a home and discharging it to the exterior.
• When equipped with a tank, a heat pump is capable of producing domestic hot water simultaneously (dual mode heap pump) or collective hot water exclusively (collective domestic hot water heat pump).
• When combined with a boiler, a heat pump can operate in hybrid mode. In this case, the heat pump mainly covers the heating requirement and the boiler takes over to produce hot water.

Working principle

A conventional heat pump consists of 5 elements:

1. A liquid refrigerant circulating inside the heat pump. This fluid changes state in each component in order to convert the energy taken from nature and transform it into heat.
2. By recovering the calories present in the external environment, an evaporator, also called “exchanger”, converts the liquid refrigerant into a gaseous state by evaporation.
3. A compressor, powered by a motor (electric or gaseous), increases the temperature of the fluid coming out the evaporator, while increasing its pressure.
4. A condenser, also called “exchanger”, transfers the energy produced during the change of state of the fluid to the outside environment. Condensation converts the gas coming out of the compressor into a liquid.
5. An expansion valve reduces the pressure of the liquid, which comes out of the condenser, so that the liquid refrigerant can start a new cycle.

Benefits of a heat pump

A heat pump draws its source of energy for free from nature. Constantly replenished by the sun, wind and precipitation, the calories taken from the environment (Air, Water or Ground) remain inexhaustible.

A heat pump alone can cover the three main needs of a home, without emitting greenhouse gases.

• heating in winter
• cooling in summer
• production of domestic hot water

Combined with a condensing boiler, a hybrid heat pump saves up to 40% energy compared to a conventional boiler.

Because of their performance and operation with renewable energies, tax incentive measures are implemented in some countries to encourage people to purchase them in the best conditions.

Following new European regulations promoting the sale of high-performance heating equipment, the performance of heat pumps is changing: the efficiency of a heat pump long characterised by an instantaneous efficiency called COP (coefficient of performance), is now characterised by a performance that reflects the efficiency of the HP throughout the year. This is known as SCOP (seasonal coefficient of performance) or ηsh (eta) for certain types of heat pumps.

Finally, this new seasonal performance is associated with energy efficiency classes (A +, A, etc.) making it easier to compare HPs with each other for each type of technology.

Compare to make the right choice

It is very easy to make the right choice: just compare the products. But when product performance is not certified, this becomes impossible.

Certification makes it possible to compare objectively.

• The product performance is evaluated according to the same criteria, and the results are expressed in the same unit of measurement, regardless of the country where the products are manufactured or marketed.
• A certified product has its performance verified by an impartial, independent and competent accredited body.
• Certified products comply with standards.
• A product whose performance is certified will work according to the specifications stated by the manufacturer.

The performances we certify

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