From 1st January 2018 stricter specifications apply for domestic ventilation units to be marketed in the European Union according to the EU regulations 1253/2014 and 1254/2014.
Since 2016, the Commission Regulations 1253/2014, defining the ecodesign requirements for ventilation units, and 1254/2014 with regard to energy labelling of domestic ventilation units, are legally binding. According to the law, manufacturers have to provide ecodesign labels for the majority of domestic ventilation systems and openly publish characteristic performance values.
With the turn of the year specific requirements for domestic ventilation units are toughened based on annex II of regulation 1253/2014. Since 1st January the following specifications apply:
a) the >> specific energy comsumption (SEC) of domestic ventilation units calculated for average climate shall be no more than â€“20 kWh/(m2Î‡a),
b) non-ducted units including ventilation units intended to be equipped with one duct connection on either supply or extract air side shall have a >> maximum sound level LWAof 40 dB,
c) all VUs, except dual use units, shall be equipped with a >> multi-speed drive or variable speed drive,
e) ventilation units with a filter shall be equipped with a >> visual filter change warning signal.
Marketing of domestic ventilation systems which do not conform with the ecodesign requirements is prohibited in the EU. More specifically, the new requirements mean the following:
a) Reduction of maximum allowed specific energy consumption (SEC):
The specific energy consumption (SEC) of domestic ventilation units is the most important characteristic value issued on the ecodesign label. Based on the SEC, calculated at average climate that predominates for example in Germany, units are categorised into energy efficiency classes from A+ (best efficiency) to G (worst efficiency). To calculate the SEC, the formula includes besides economic factors and physical properties also various characteristics and configurations of the ventilation unit. The specific electric power consumption of the unit as well as the recovery of heating energy of the heat exchanger, which is implemented into the ventilation unit, are the important variables. Additionally the system of heat recovery (recuperator or regenerator), the regulation of the fan, the control of the unit (demand, clock or manual control) and the general typology (whether air is conducted with or without air ducts) are included into the formula.
The calculated SEC is in most cases a negative value, since it is supposed to demonstrate the possible saving of primary energy per year and square meter living space with the usage of a domestic ventilation unit in comparison to conventional heating methods. The lower the value, the more primary energy can theoretically be saved with the ventilation unit.
Figure 3 shows, how the new minimal requirement of the SEC affect the classes. Domestic ventilation systems, which are categorised in the classes E, F and G, must not be marketed in the EU beginning with 1st January 2018. This requirement only appliesto units with an electric power input of less than 30 W per air stream.
SEC values of the classes E, F and G are reached by unidirectional domestic ventilation units (either supply or exhaust air) without heat recovery which save energy only by ensuring a controlled ventilation of the dwelling. Most, if not all, of these units do not come under this regulation because of their low electric power input or other characteristics. Bidirectional ventilation units with heat recovery that realise both the supply and exhaust air flows are mostly categorised into the classes from B to A+ and are thus not affected by the stricter regulation.
b) Lowering of the maximum allowed sound level LWA:
To keep up the living comfort of residents and prevent noise nuisance of the ventilation unit, the operation of the unit without perceptible acoustic emission into the dwelling must be realised. For centralised units with ducted supply and exhaust air flows, an operation without disturbing noise levels is highly dependent on orderly planning, installation and maintenance of the unit by craftsmen, conforming to technical standards.
For decentralised units, which are at at least one air flow side directly connected to an interior room, the emission of acoustic power from the casing to the dwelling must not disturb the inhabitants in normal operation. By toughening the regulation 1253/2014, the commission instructed that such ventilation units must not emit more than 40 dB (A) of acoustic power from the casing into the interior. For the evaluation of acoustic levels for ecodesign requirements, the sound level emitted by the casing of the ventilation unit at reference volume flow is used. The reference volume flow is the volume flow conductible by the unit at 50 Pascal (for units with ducts) or a minimum pressure (for units without ducts) that lies closest to, but at at least 70 percent of the highest possible volume flow. This means that the acoustic level of the unit at the maximum volume flow can be higher than the benchmark issued on the ecodesign label.
It has to be annotated as well that many of those units, for which the limits of sound emission could become critical, do not come under this regulation due to their general configuration. In most cases unidirectional supply or exhaust air units, which are installed adjacent to interior rooms, have an electric power consumption of below 30 W per air stream.
c) Necessity of multi-speed drive or variable speed drive:
Fans should always lead enough fresh air into the dwelling to satisfy the current demand in the living area. Only an adequate exchange of air the building safety and the health and comfort of the inhabitants can be secured. For a highly efficient operation without unnecessary energy usage, the prevalent needs of ventilation should be met without excessive air conduction. It is important that the fans in the domestic ventilation unit are equipped with a sufficient quantity of speeds or a variable speed drive to adapt the air flow rate to the demand.
In the ecodesign for domestic ventilation units this aspect is factored in on the one hand by the inclusion of the so-called x-value as a parameter in the formula for the SEC. This only applies, if the unit operates with a better control than a mere manual adjustability by the user. The more speeds the fan can realise, the lower the calculated annual energy consumption turns out. According to the formula a variable speed drive is the most energy saving.
On the other hand, since 2016 no units with less than three different speeds plus the speed 0 (off) may be sold in the EU. This requirement remains in force in 2018.
d) Facility for thermal by-passing as a necessary component of the domestic ventilation unit:
During hot days, especially in summer, a heat recovery by the unit, which would lead to a further temperature rise in the interior, can be undesirable. Thus, supply and exhaust air units in most cases have a thermal by-pass included which prevents the heat exchange from exhaust to supply air.
According to ecodesign requirements as stated in the regulation 1253/2014 bidirectional domestic ventilation units, meaning supply and exhaust air units, that shall be sold in the EU, must have a thermal by-pass facility implemented. A facility of this kind is defined in the regulation as follows: â€žany solution that circumvents the heat exchanger or controls automatically or manually its heat recovery performance, without necessarily requiring a physical airflow bypass (for example: summer box, rotor speed control, control of air flow).â€œ
The thermic by-passing of heat recovery can be realised with different facilities or configurations. Many units consist of a manually or automatically activatable by-passing function which leads either the supply or exhaust air flow through the unit without passing the heat exchanger. Another solution, often used by older units, is a so called summer box. This has to be manually implemented by the user into the unit to divert the air flow. Also with temperature dependent configurations of the air stream or the fan rotation the heat recovery can be reduced or, for example by temporarily switching off one air flow side, fully prevented. Reversible decentralised ventilation units achieve a thermal by-passing by temporarily switching to a non-reversing constant flow at which one unit conducts the supply air and the other the exhaust air flow.
e) Equipment of domestic ventilation units with a visual filter change signal:
Domestic ventilation units with at least one filter included to protect the unit as well as the living space from pollutants, must be equipped with a visual filter change signal since 1st January 2018. Principally, every domestic veniltation unit should have a filter implemented to clean the air since hygiene and as a consequence the health of the inhabitants are two of the most important assets of these units. Additionally, the units themselves should also be protected from pollution.
Most bidirectional ventilation units lead air through a medium or fine filter to clean the supply air to filter off dust, pollen or fine particles. In most cases there is also a coarse filter in the exhaust flow side before the heat exchanger to prevent pollution of the unit. For the same reasons, at least one filter should be included into unidirectional supply or exhaust units.
Because filter pollute during operation of the unit, which leads to a lowering of the delivered volume flow or higher energy costs, they need to be exchanged with new, clean filters regularly, in most cases once or twice every year. Filter pollution is surveilled by the unit, for example with a counter of operating hours or measuring of pressure losses. Is a filter change necessary, an acoustic or visual signal indicates this. In compliance with the regulation, all new domestic ventilation units need to be equipped with a visual filter change signal.
The ecodesign regulations do not define, where this optical display has to occur. Possible placements for the signal can be directly on the unit, on the display in the living space or, for units controllable with computers, tablets or smartphones, by notification in the program or app. The first option is not adequate for a regular check of the filter status, because most bidirectional ventilation units are installed in a separate utility room, the basement or the attic.
Further toughening of ecodesign requirements for domestic ventilation units is yet to be discussed
With the requirements as they are in effect since the beginning of 2018, the ecodesign regulations 1253/2014 and 1254/2014 for domestic ventilation units reached their final status for the time being. Nonetheless, in Article 8, Review, of the former regulation the future planning of the Commission for the ecodesign is envisaged to cope with technical progress. At latest on 1st January 2020 during a review of the regulations a further toughening shall be discussed. This review considers among others a) an enhancement of the ecodesign to units with low power input, b) factoring in of the effect of filters with little impact on the energy efficiency in the calculation of the SEC and c) stricter requirements for ecodesign of domestic ventilation units.