EN 15241:2007

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Lüftung von Gebäuden - Berechnungsverfahren für den Energieverlust aufgrund der Lüftung und Infiltration in GebäudenVentilation des bâtiments - Méthodes de calcul des pertes d'énergie dues a la ventilation et a l'infiltration dans les bâtimentsVentilation for buildings - Calculation methods for energy losses due to ventilation and infiltration in buildings91.140.30VLVWHPLVentilation and air-conditioningICS:Ta slovenski standard je istoveten z:EN 15241:2007SIST EN 15241:2007en01-oktober-2007SIST EN 15241:2007SLOVENSKI
STANDARD
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 15241May 2007ICS 91.140.30 English VersionVentilation for buildings - Calculation methods for energy lossesdue to ventilation and infiltration in commercial buildingsVentilation des bâtiments - Méthode de calcul des pertesd'énergie dues à la ventilation et aux infiltrations dans lesbâtiments commerciauxLüftung von Gebäuden - Berechnungsverfahren für denEnergieverlust aufgrund der Lüftung und Infiltration inNichtwohngebäudenThis European Standard was approved by CEN on 26 March 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2007 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15241:2007: E

A simplified model of a Ground to Air Heat Exchanger.21 A.1 Background and summary.21 A.2 Overview of program links, variables, parameters and constants.22 A.3 Physical description of the ground to air heat x-change model.23 Bibliography.26

Existing national regulations with or without reference to national standards, may restrict for the time being the implementation of the European Standards mentioned in this report According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

Figure 1 - Scheme of relationship between standards Table 1 - Relationship between standards from To
Information transferred variables 15251 15243 Indoor climate requirements
Heating and cooling Set points
13779 15251 15242 Airflow requirement for comfort and health Required supply and exhaust Air flows 15242 15241 Air flows Air flows entering and leaving the building 15241 13792 Air flows Air flow for summer comfort calculation 15241 15203- 15315 ;15217 energy Energies per energy carrier for ventilation (fans, humidifying, precooling, pre heating), + heating and cooling for air systems 15241 13790 data for heating and cooling calculation Temperatures, humilities and flows of air entering the building 15243 15243 Data for air systems Required energies for heating and cooling
15243 15242 Data for air heating and cooling systems Required airflows when of use 15243 13790 data for building heating and cooling calculation Set point, emission efficiency, distribution recoverable losses, generation recoverable losses 13790 15243 Data for system calculation Required energy for generation

4 Symbols and abbreviations Table 2 — symbols and abbreviations Symbol Unit descriptionA m² area Bh m building height Cductleak ad coefficient taking into account lost air due to duct leakages Csyst ad coefficient taking into account the component and system design tolerances Cuse ad coefficient taking into account the switching on and off of fans Ccont ad coefficient depending on local air flow control Eff ad efficiency H W/K heat loss qv(dP) curve or airflow/pressure difference characteristic
formula
qv 4Pa,n or m3/h external enveloppe airtightness expressed as an airflow for a given pressure n50,n
difference, exponent qv 4Pa,n or m3/h partial air tightnesss for altitude (z), orientation (or), tilt angle (Tilt) n50,n
qv-exh m3/h exhaust air flow
qv-sup m3/h supply air flow P W heating power R Ad ratio θ °C temperature x g/kg of dry air moisture content of the air

5 General approach EN 15242 defines the procedure to calculate the following air flows (either entering or leaving the heated/conditioned area) through leakages, opened windows, purpose provided openings (considered as part of the ventilation system) and the ventilation system. For overall heating and cooling needs calculation, prEN ISO 13790, uses directly the airflows entering the building through leakages, opened windows, and purpose provided opening, as there's is no additional energy impact when these air flows are known. Therefore this standard focuses on the impact on the ventilation system itself both for the air treatment and move. For air heating and cooling system, prEN 15243 provides the required airflow and supply temperatures.
23415 Key 1 ventilation system 4 leakage 2 window opening 5 internal reference pressure 3 opening
Figure 2 — general scheme for airflows

preheating, precooling, humidifying, dehumidifying;  The heating and cooling energy needs due to infiltration are not part of the standard. Required energy for heating and cooling for air heating and cooling systems can be taken into account using the same formulas in connection with prEN 15243. These energies will be provided by energy carrier and use (heating, cooling, ventilating). In some cases it will require some specific assumptions as for example if a fan is used for ventilation, heating and cooling.
Three implementation possibilities of the calculation procedure described in Clause 6 are shown in Clause 7.
6 Steady state calculation 6.1 Basis of the calculation method Starting from the airflows, the aim of the procedure is to calculate:  Temperature and humidities of the airflows entering the heated or cooled areas.  Energy devoted to the air treatment. 6.2 Air entering through infiltration, passive air inlets or windows It is basically considered that the air characteristics are the outdoor air ones.
Preheated air inlets and ground coupling are part of this standard If the air is taken in an adjacent space the air temperature in this space shall be calculated according to prEN ISO 13790. 6.3 Air entering through balanced or supply only system calculation 6.3.1 General The following subclauses describe how the air characteristics are modified in each component, and the energy required for that treatment.

∆Tduct
is the difference in air temperature between the inlet and the outlet of the duct, in K θ1,x1
are the air temperature and humidity at the inlet of the duct, (in °C and g/kg of dry air) θ2,x2
are the air temperature and humidity at the outlet of the duct, (in °C and g/kg of dry air) ∆Tduct
is calculated by
)1)(().34,0(1vductductqHsurductducteT−−−=∆θθs where
θsurduc
is the temperature of the air surrounding the duct, equal in this case to the outdoor air temperature, in °C Hduct
is the heat loss from the duct to the surrounding, in W/K
qvduct
is the rate of air flow in the duct, in (m³/h)
6.3.3 Duct flow losses The infiltred or exfiltred flow into or from the duct is calculated according to EN 15242. If the air is exfiltred, there is no change in air characteristics in the duct (but a difference in air flows). If the air is infitred, the outdoor air is mixed to the air entering the duct. 6.3.4 Fan
The air temperature is increased by the fan of a ∆Tfan
value
where: ∆Tfan
is the increase of air temperature caused by fan, in K, Ffan
is the fan power, in W, Rf,r
is the fan power recovered ratio (ad.), ρ c
is the product of the air density and the specific heat, in 34 W
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