How does a heat pump work?

Heat pumps are innovative devices whose usefulness is no longer to be demonstrated, especially when it comes to air conditioning and heating. They constitute a more effective, more ecological and more economical alternative, responding faithfully to the energy needs of households, in a society where energy transition and global warming are at the heart of concerns.

However, their operating principle remains a mystery for more than one, a mystery that is important to elucidate in order to better orient your choices.

The heat pump: definition and operating principle

Heat pump is a device that uses air or water to produce heat or fresh air. According to several studies, this device can alone generate 75% of the heat required in a household.

However, before installing a heat pump at home, it is essential to understand how it works.

A heat pump contains a refrigerant liquid whose boiling temperature is very low (between -10 ° C and -50 ° C approximately). This refrigerant is in a closed circuit. In contact with the outside air, it will warm up and go from the liquid state to the state of steam. This heat will then be used to heat the house, which will cool it and have it ironed in the liquid state. The cycle will then be able to start again.

A heat pump includes four main elements: the evaporator, the compressor, the condenser and the holder.

The evaporator is a device that captures the heat of the environment (water, air, soil), makes it pass through a system containing a refrigerant fluid in order to pass it from liquid to the gas state. The gas produced is then sucked up by the compressor which increases the pressure and consequently the temperature. We then obtain a heated gas which then passes through the condenser which will cool it using its heat to heat the house. By cooling, the refrigerant will condense and return to the liquid state. At the same time, the holder takes care of lowering the pressure of the cooled liquid to prepare it to restart the cycle.

Heat pump varieties and their particularities

Heat pumps are available in several models, each with distinct characteristics.

The air-to-air heat pump

This model draws heat from the outside air, amplifies it and transfers it inside the house through a ventilation system. It is generally used as a complementary solution to the electric heating system. It is therefore an easy to install and less expensive device.

The air-water heat pump

The air-water heat pump is also a model using air as an energy source from which it draws the heat necessary for the heating of the house. Nevertheless, what distinguishes it is the way in which heat is diffused, using hydraulic systems such as heated floors or radiators. Although its installation is more complex and more expensive, it offers the advantage of providing both heating and DHW (domestic hot water).

Reversible heat pump

The reversible heat pump is a device that alone incorporates two functions: the air conditioning function and that of heating. In winter, it transfers the heat drawn from the outside to the rooms of the accommodation, and reverses the process in summer (the inner heat is rejected outwards).

Note that there are several other types of heat pumps, including geothermal models (soil-water or soil-to-air), hydrothermal (water water) and even hybrid heat pumps.

The essential criteria for choosing the right heat pump

Before investing in a heat pump, make sure you understand the needs of your home in terms of air conditioning and heating. To do this, several elements must be taken into account:

• Housing size
• The quality of the insulation
• The cost of equipment
• The type of heat pump
• Purchase, installation and operating costs
• The energy efficiency of the device, etc.

Do not hesitate to call on a professional who will accompany you more effectively in this approach.