In box
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Indoor unit (hydromodule). The part of a heat pump that is installed indoors. By definition, it is included in the delivery set of "ground-water" units (see "Heat source") — the indoor unit, in this case, is the actual heat pump, only the collector and connecting pipes are brought out. But air models may not have this module.
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Outdoor unit. It is not used in ground-to-water models. However, it is an almost obligatory element of a complete set for air-to-water units. Usually, the outdoor unit also includes a collector for heat extraction. However, there are air heat pumps that can be installed indoors, with air supply and exhaust through ventilation ducts. — however, for such models, only the indoor unit is indicated in the package, although the device can usually be installed outdoors. And there are even
monoblock models that combine an indoor and outdoor unit in one case.
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Water heater. A device for heating water and supplying it to the DHW system; see "Water heater" for details. The presence of a built-in water heater, on the one hand, simplifies the installation of the pump and eliminates the need to purchase additional equipment; on the other hand, when buying such a pump, you have to rely on the choice of the manufacturer, while an external water heater can be purchased separately.
Max. heat output
The maximum heat output generated by a heat pump is the amount of heat it can transfer from the outdoors into the heating system and/or domestic hot water.
The heat output is the most important spec of a heat pump. It directly determines its efficiency and ability to provide the required amount of heat. Note that this spec is shown for optimal operating conditions. Such conditions are rare, so the actual output heat is usually noticeably lower than the maximum; this must be taken into account when choosing. There are special formulas for calculating the optimal value of the maximum heat output, depending on the specific condition.
Max. cooling output
Maximum cooling output delivered by the pump.
The pump operates in the cooling mode removing excess heat from the room to the environment — it plays the role of an air conditioner. The required cooling capacity depends on the area of the building, the specs of its thermal insulation and some other factors; methods of its calculation can be found in special sources. Also note here that conventional heating equipment (radiators, underfloor heating) is not suitable for cooling, for this it is necessary to use special equipment (for example, fan coil units).
Power consumption (heating)
Electric power consumed by the heat pump when operating only for heat transfer, without the use of an additional heating element (if any, see below). The ratio of thermal power to power input determines the thermal coefficient COP (see below) and, accordingly, the overall efficiency of the unit. It also affects overall power consumption (and therefore electricity bills), as well as some power and connection requirements — for example, models powered by 230 V and with a power of more than 5 kW cannot work from an outlet and require a special connection to the mains.
Power consumption (cooling)
For more information on power consumption, see the paragraph above. Here is indicated the consumption of electricity during operation in the cooling.
Minimum operating temperature
The lowest ambient temperature (air or ground, see Heat source) at which a heat pump can safely and reasonably efficiently perform its functions. Efficiency at minimum temperature, of course, is noticeably reduced, but the device can still be used as a heat source.
The data on the minimum operating T allows you to evaluate the suitability of the pump for the cold season.
Max. water temperature
The highest temperature to which the pump can heat the coolant. It is worth noting that such indicators can be achieved at a fairly high temperature of air or ground. And since heat pumps are used during the cold season, the actual maximum temperature, usually, is less than theoretically achievable. Nevertheless, this parameter makes it possible to evaluate the capabilities of the unit or its suitability for certain tasks.
Supply t°C
The temperature in the flow pipe for which the COP is specified. See below for more details on this coefficient. And this temperature is the temperature of the heat carrier at pump outlet, at which the given COP value is reached.
Note that manufacturers often go to the trick and measure COP for a relatively low temperature (much lower than the maximum temperature of the heat carrier — for example, 35 °C for a model with a maximum of 55 °C). This allows them to give quite impressive performance figures in the specifications. However, at higher temperatures, the actual energy cost per unit of thermal power will be greater and the actual COP will be lower.
COP
The COP (coefficient of performance) is a key characteristic that describes the overall efficiency of a heat pump. It represents the ratio between the thermal power and power consumption of the unit (see above) – in other words, how many kilowatts of thermal energy the pump produces per 1 kW of electricity consumed. In modern heat pumps, this figure can exceed 5.
However, note that the actual COP value may vary depending on the outside temperature and the supply temperature. The higher the difference between these temperatures, the more resources are needed to “pump” thermal energy and the lower the COP will be. Therefore, in the specifications it is customary to indicate the COP value for specific temperatures (and in many models – two values, for different options) – this allows you to evaluate the actual capabilities of the unit.
