A heat pump is a device that draws heat energy from the building's surroundings (air, ground or water) and transfers it to the central heating installation. In this way, it obtains clean, ecological energy at low costs (electricity used to power the compressor). It is used for heating the building, utility water, and also for cooling rooms in hot weather. While looking for a comfrotable and cheap solution for heating of your home we often think about using a heat pump. First of all, we want the heat pump to provide lower costs of our heating and we want it to be relaialble to us for several decades. This is fully justified because the prices of traditional fuels are changing rapidly. They are getting higher every year and it is difficult to predict what the situation will be in the next few years. Two-thirds of the cost of maintaining a building are related to the heating. By using an inexpensive heat source, such as heat pumps, we can ensure low heating costs for up to 50 years. Currenlty heat pumps are a reliable, economical and environmentally friendly source of heat with a guaranteed future. In Switzerland, every third house is already equipped with a heat pump.