Boiler combination heater

A ‘boiler combination heater’ is a boiler space heater that is designed to also provide heat to deliver hot drinking or sanitary water at given temperature levels, quantities and flow rates during given intervals, and is connected to an external supply of drinking or sanitary water.

Boiler combination heater

Rated heat output (Prated) of boiler (in kW)

Rated heat output (Prated) of the boiler space or combination heater (in kW)

The ‘rated heat output’ means the declared heat output of the heater when providing sapce heating at standard rating conditions, expressed in kW. It can be found in the product label (box on the bottom right-side), expressed in kW. It can also be found in the 'product fiche', usually indicated as 'Prated'. The size may vary, usually between 3 and 30 kW and shall not exceed 70 kW.

Seasonal space heating energy efficiency of boiler (in %)

Seasonal space heating energy efficiency of the boiler space or combination heater (in %)

The 'seasonal space heating energy efficiency’ means the ratio between the space heating demand for a designated heating season, supplied by a space heater, and the annual energy consumption required to meet this demand, expressed in %. It can also be identified as (ηs) and it can be found in the 'product fiche'.

Water heating energy efficiency of water heater (in %)

Water heating energy efficiency of water or combination heater (in %)

‘Water heating energy efficiency’ means the ratio between the useful energy provided by a water heater or a package of water heater and solar device and the energy required for its generation, expressed in %. It can also be identified as (ηwh) and it can be found in the 'product fiche'.

Declared load profile

The load profile declared by the manufacturer for the water heater can be found on the product label or the product fiche. For the calculation of the water heating package, only water heaters with a load profile between M and XXL are applicable.

Temperature control

The 'temperature control’ means the equipment that interfaces with the end-user regarding the values and timing of the desired indoor temperature, and communicates relevant data to an interface of the heater such as a central processing unit, thus helping to regulate the indoor temperature(s).

Temperature control

Temperature Control (Class)

The temperature controls can be classified differently depending on their functioning, from a class I for the more simple “On/off“ room thermostat up to a class VIII for Multi-sensor room temperature controls, for use with modulating heaters. More details regardng the different classes can be found here [link].

Supplementary boiler

A ‘supplementary heater’ means a non-preferential heater that generates heat in cases where the heat demand is greater than the rated heat output of the preferential heater. In this case, the supplementary heater would be a second boiler. A ‘boiler space heater’ is a space heater that generates heat using the combustion of fossil fuels (gas, oil) and/or biomass fuels, and/or using the Joule effect in electric resistance heating elements.

Supplementary boiler

Rated heat output (Prated) of the supplementary boiler (in kW)

The ‘rated heat output of supplementary heater’ means the declared heat output of the supplementary heater when providing space heating at standard rating conditions, expressed in kW. It can also be found in the 'product fiche', usually indicated as 'Psup'.

Seasonal space heating energy efficiency of supplementary boiler (in %)

Same explanation as for the the ‘Seasonal space heating energy efficiency of boiler', used above. In this case it refers to the suplementary (or secondary) boiler.

Solar device

A ‘solar device’ means a solar-only system, a solar collector, a solar hot water storage tank or a pump in the collector loop, which are placed on the market separately

Solar device

Solar collector area (in m2)

The information about the area of a solar thermal collector can be found in the 'product fiche'. It is indicated in m² (square metres). To reach the total collector area, the collector area (per unit) should be multiplied by the total number of collectors installed (collector area (m² per unit) * no. of collectors).

Solar collector efficiency (in %)

The solar collector efficiency should be indicted in the 'product fiche'. Alternatively, it can be found in test results of the solar collector that can be found as annexes to the Solar Keymark certificates.

Annual non-solar heat contribution (Qnonsol)(in kWh)

The Qnonsol value might be found in the 'solar device' product fiche. In case the product fiche is not available, the Qnonsol parameter can be calculated using the support tool (SOLCAL), using data regarding the solar thermal collector, the hot water store, the water pump and the control. This calculation might be harder for a person without professional or specialized knowledge in this subject.

Auxiliary electricity consumption (Qaux)(in kWh)

The Qaux value might be found in the 'solar device' product fiche. In case the product fiche is not available, the Qaux parameter can be calculated using the support tool (SOLCAL), using data regarding the solar thermal collector, the hot water store, the water pump and the control. This calculation might be harder for a person without professional or specialized knowledge in this subject.

Heat storage tank

A ‘hot water storage tank’ is a vessel for storing hot water for space heating purposes, including any additives, which is not equipped with any heat generator except possibly one or more back-up immersion heaters.

Heat storage tank

Volume of the heat storage tank (in l)

The size of the hot water storage tanks is indicated in terms of volume (litres). This information can be found in the product label (information box at the bottom of the label) or in the product fiche.

Tank label class

The energy label class of the hot water storage tanks ranges from G to A. This information can be found in the product label or in the product fiche.

Supplementary heat pump

‘Heat pump’ means a space heater using ambient heat from an air source, water source or ground source, and/or waste heat for heat generation; a heat pump space heater may be equipped with one or more supplementary heaters using the Joule effect in electric resistance heating elements or the combustion of fossil and/or biomass fuels. A ‘supplementary heater’ means a non-preferential heater that generates heat in cases where the heat demand is greater than the rated heat output of the preferential heater. In this case, the supplementary heater would be a heat pump.

Supplementary heat pump

Rated heat output (Prated) of the supplementary heat pump (in kW)

Same explanation as for the the ‘rated heat output’ of the boiler, used above. In this case it refers to the suplementary (or secondary) heater, which is the heat pump. In the product label, it is indicated as the value fro the average climate on the bottom, next to the European map (temperature map displaying three indicative temperature zones).

Seasonal space heating energy efficiency of supplementary heat pump (in %)

Seasonal space heating energy efficiency’ means the ratio between the space heating demand for a designated heating season, supplied by a space heater and the annual energy consumption required to meet this demand, expressed in %. This value should be indicated in the 'product fiche' and is indicated as a value for average climatic conditions and temperatures, either 35° or 55°, based on actual load profile (i.e., the demand of the heating system). There are three options in terms climatic conditions: Colder (Northern Europe), Average (Central Europe), Warmer (Shouthern Europe).

Calculate / pdf

The option «Calculate» allows access to the preliminary version of the label, allowing still editing and changes of the inserted data. The option «PDF» redirects to a new web page where the user must enter the product information that will be shown on the label: make and models of the system components & system supplier.

Calculating Package Efficiency and Class

Boiler combination heater