How effective are heat pumps in summer?

Are MultiTherma heat pumps effective in summer?

Heat pumps are commonly associated with heating buildings in the winter season. Their functionality, however, is not limited to the colder months. In fact, heat pumps can be equally effective in summer — offering room cooling, domestic hot water (DHW) heating, and even pool heating or pre-cooling of air in ventilation systems.

How MultiTherma heat pumps work in summer compared with winter

MultiTherma heat pumps work on the principle of a reversed thermodynamic cycle. In summer the unit takes heat from inside the building and releases it outside — much like an air conditioner. In winter it is the opposite: it draws heat from the outside air and transfers it indoors. Thanks to the use of the refrigerant R290, multi-point refrigerant injection into the evaporator and a wide capacity-modulation range, MultiTherma offers high efficiency in both operating modes.

The ability to act as air conditioning

MultiTherma pumps can work as full-fledged air conditioning. Combined with fan coils, they allow precise room cooling. It is also possible to use underfloor heating or even radiators for cooling — while keeping the water temperature in the system above the dew point (~18 °C). Although the effect is then not as intense as with fan coils, it provides noticeable comfort with no additional investment costs.

Ustawienia dla efektywnej pracy latem

MultiTherma, just like classic chillers, can produce chilled (ice) water even at parameters of 6/12 °C — so it can effectively replace them in projects. Cooling efficiency is greater the higher the cooler temperature, so it is beneficial to design fan coils for higher water parameters, e.g. 10/17 °C. In newly built homes, alongside surface heating it is worth also considering fan coils — for a small cost we gain fully functional, efficient air conditioning. In renovated buildings, existing radiators or underfloor heating with water ≥18 °C can be used, achieving a significant improvement in summer comfort with minimal energy use and no additional investment.

Effective cooling time during prolonged heatwaves

Thanks to multi-point refrigerant injection into the evaporator, MultiTherma has no operating limits at high temperatures — in line with its cooling-mode operating envelope it works efficiently up to +45 °C. So it can work all summer without trouble, even during extreme heat, whether heating a pool or DHW or in air-conditioning mode. It is worth remembering that in Polish conditions, cooling-mode operation accounts for only about 4% of annual energy demand.

Running costs of MultiTherma heat pumps

MultiTherma’s energy efficiency is very high. For example, for the MultiTherma 12 HD model the seasonal SCOP wynosi 4,83, a SEER 3,59. This means that over the whole season the pump delivers, on average, almost five times more heat energy than the electricity it uses during the heating season, and almost four times more cooling energy in summer. If the building has photovoltaics, for most of the year a significant amount of the energy to run the pump can come from free solar energy.

Annual energy demand — a case study for a 200 m² house

For a house with a heated area of 200 m² in Poland’s climate zone III, the annual energy demand breaks down roughly as in the chart below. The averaged year-round system efficiency is about 4.19.

MultiTherma heat pumps are versatile and efficient devices that provide year-round thermal comfort: heating in winter, cooling in summer and DHW heating all year. In buildings with photovoltaics, a significant part of the energy can come from a free source — solar radiation. MultiTherma to zatem nie tylko wygoda, ale także świadoma i przyszłościowa inwestycja w energooszczędny dom.

← Back to news