Heating with a heat pump

Heat pumps are energy-efficient equipment that will ensure a comfortable indoor temperature at any time of the year. Since in winter, the heat pump will work to heat the building, and in summer to cool it. In addition, the equipment can heat water and provide residents with hot water for household and other needs all year round.

There are several types of heat pumps. They differ in the principle of operation of the system, heat source, etc. In addition, each type of equipment has special installation requirements, its advantages and disadvantages.

There are the following types of heat pumps:

The main characteristic of efficiency relating to heat is the COP (Coefficient of Performance), which depends on the air temperature. The closer the air temperature is to 0 °C, the greater the COP.
When it comes to house cooling, the characteristic is EER (Energy Efficiency Ratio).

Additional equipment for the fast generation of cold or heat for an air-to-water heat pump: fan coil units; radiators; in-floor convectors. Selection of radiators should be carried out no higher than +45 °C.

When purchasing a heat pump with its implementation using underfloor heating, radiators and in-floor convectors, you will not be able to perform the function of cooling the house for the summer period. For the efficient operation of the equipment, it is necessary to use a heat pump while considering all its functions: heating/cooling, heating water for hot water supply. Therefore, for the productive operation of the heat pump, it is necessary to replace the radiators with floor-standing fan coil units, which can work for both heating and cooling the room.

A heat pump for heating is a low-temperature equipment that works with underfloor heating. Thus, the lower the supply temperature, the more efficient the heat pump itself.

The temperature of the underfloor heating should not exceed +24-26 °C. Since when the temperature of the floor surface increases, the inertia of the uneven temperature difference will occur and the floor will become too hot, which will bring discomfort to the foot. If wooden floors are laid in your house, in-wall heating or the selection of the optimal type of floor covering will be an alternative in order to provide the high quality functioning of the heating system with a heat pump.

Let us consider the algorithm of operation of the air-to-water heat pump equipment.

The unit can work for both heating and cooling. Regarding cooling, the algorithm of work occurs in the reverse order. The indoor unit will become an evaporator, and the outdoor unit will become a condenser.

The temperature of the heat carrier for the fan coil unit, which works for cooling, is + 7 °C. Calculations in the selection of equipment are made for +9 °C.
The maximum heat carrier temperature for efficient operation of the air source heat pump in heating mode should be +40 °C.
The calculation of the floor part of the fan coil unit is made for + 40-45 °C, since the thermotechnical calculation is made for up to -7 °C, and then an auxiliary device, for example an electric boiler, is turned on.

A fan coil unit is considered an energy-efficient device that works both for cooling and heating rooms to a predetermined temperature. This equipment is considered the best option for installation in houses, and it will create comfortable living conditions, despite the time of year and the room area.

Floor-mounted fan coil units are considered the best purchase, since the equipment is installed along the double-glazed window. Such installation will provide an opportunity to avoid maximum cold/heat gain into the house.

For the living room, the best option is to install a ducted air conditioning system.

An air-to-air heat pump is considered a fairly common type of device, but is suitable for small buildings. It is necessary to consider that it will be impossible to completely heat/cool a country house or a cottage. The equipment is one of the budget types of heat pumps, since the prices for the purchase of the unit are considered quite affordable. A heat pump for heating is a system that consists of an indoor and outdoor unit.

The outdoor unit is responsible for taking heat from the cold outside air and heating the Freon. The indoor unit contributes to the supply of heat from Freon to the room air. There are several types of indoor units. They may be:

The heat pump can work both for heating and for cooling the room. An air-to-air heat pump for heating can sometimes bring discomfort to a person and lower the level of comfort in the house, since hot air is distributed unevenly around the perimeter of the room.

In addition, the equipment is widely used in countries where there are no severe frosts. Therefore, Alter Air specialists recommend using an air-to-water heat pump, since an air-to-air heat pump loses its effectiveness in the Ukrainian climate.

The air-to-water heat pump is a universal and popular device that is in high demand for use in Ukraine. An air-to-water heat pump, like an air-to-air heat pump, has an indoor and outdoor unit. However, if we compare these heat pumps in terms of their functions, then, unlike air, water can work not only for heating/cooling the room, but also for heating water for hot water supply. 

Basically, for a full-fledged heating system, the equipment is used with underfloor heating, in-wall heating, and fan coil units.

Underfloor heating is considered as an additional device for the comfort in the house. The surface of the floor should be in the range of + 24-26 °C, since this is the optimal temperature for the foot, and it compensates for the heat loss of the building. With the use of underfloor heating, the heating system can work as a full-fledged source of heat, up to approximately -10 °C outside. 

However, it is unwise to consider underfloor heating as the only source of heat. With a sharp cold snap, the floor temperature will rise above + 26 °C. In addition, when the temperature rises outside, the warm floor will turn off. However, the heat source, like heated concrete, will continue to generate heat, which will lead to inertia of the floor.

If the atmospheric temperature is less than -10 °C, Alter Air recommends using a heat pump for heating with a combination of equipment such as a fan coil unit. With such a heat source, it is possible to regulate the heat supplied by the thermostat, or on the device itself.

It is important to remember that using a heat pump only for home heating is considered irrational. Since the outdoor and indoor units can provide the supply of both cold and heat to the room.