SIST EN 13141-4:2021

SLOVENSKI STANDARD
01-junij-2021
Nadomešča:
SIST EN 13141-4:2012
Prezračevanje stavb - Preskušanje lastnosti sestavnih delov/izdelkov za
prezračevanje stanovanjskih stavb - 4. del: Aerodinamične, električne in akustične
lastnosti enosmernih prezračevalnih enot
Ventilation for buildings - Performance testing of components/products for residential
ventilation - Part 4: Aerodynamic, electrical power and acoustic performance of
unidirectional ventilation units
Lüftung von Gebäuden - Leistungsprüfungen von Bauteilen/Produkten für die Lüftung
von Wohnungen - Teil 4: Aerodynamische, elektrische- und akustische Leistung von
unidirektionalen Lüftungsgeräten
Ventilation des bâtiments - Essais des performances des composants/produits pour la
ventilation des logements - Partie 4 : Performance aéraulique, de puissance électrique et
acoustique des unités de ventilation simple flux
Ta slovenski standard je istoveten z: EN 13141-4:2021
ICS:
91.140.30 Prezračevalni in klimatski Ventilation and air-
sistemi conditioning systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 13141-4
EUROPEAN STANDARD
NORME EUROPÉENNE
April 2021
EUROPÄISCHE NORM
ICS 91.140.30 Supersedes EN 13141-4:2011
English Version
Ventilation for buildings - Performance testing of
components/products for residential ventilation - Part 4:
Aerodynamic, electrical power and acoustic performance
of unidirectional ventilation units
Ventilation des bâtiments - Essais de performance des Lüftung von Gebäuden - Leistungsprüfungen von
composants/produits pour la ventilation des Bauteilen/Produkten für die Lüftung von Wohnungen -
logements - Partie 4 : Performance aéraulique, de Teil 4: Aerodynamische, elektrische und akustische
puissance électrique et acoustique des unités de Leistung von unidirektionalen Lüftungsgeräten
ventilation simple flux
This European Standard was approved by CEN on 25 January 2021.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC 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
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 13141-4:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Introduction . 6
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 Symbols and abbreviations . 11
5 Performance testing of aerodynamic characteristics . 13
5.1 External leakages . 13
5.1.1 Test installation . 13
5.1.2 Test procedure . 13
5.2 Air flow/pressure performance . 15
5.2.1 General . 15
5.2.2 Test Installation . 16
5.2.3 Test procedure . 17
5.3 Air flow sensitivity . 21
5.4 Indoor/outdoor airtightness . 22
6 Energy. 22
6.1 Performance testing of electrical power . 22
6.1.1 Testing method . 22
6.1.2 Electrical power input at reference and maximum air volume flow . 22
6.1.3 Assessment of part load energy efficiency (optional) . 22
6.2 Operable mode . 22
6.3 Standby mode . 22
7 Performance testing of acoustic characteristics . 23
7.1 General . 23
7.2 Noise radiated through the casing of the unit L . 25
Wc
7.2.1 General . 25
7.2.2 Test Installation . 25
7.2.3 Measurements . 26
7.3 Radiated sound power level in the indoor or outdoor space – L and L . 27
Wi Wo
7.3.1 General . 27
7.3.2 Test Installation . 27
7.3.3 Measurements . 29
7.4 In-duct sound power level of the unit . 29
7.4.1 General . 29
7.4.2 Test Installation . 29
7.4.3 Measurements . 31
7.5 Airborne sound insulation . 31
7.5.1 General . 31
7.5.2 Test Installation . 31
7.5.3 Measurements . 32
8 Test results . 32
8.1 Test report . 32
8.2 Product specifications. 32
8.3 Leakages . 33
8.4 Air flow/pressure curve . 33
8.5 Air flow sensitivity for non-ducted ventilation units . 33
8.6 Indoor/outdoor airtightness for non-ducted ventilation units . 33
8.7 Energy . 33
8.8 Acoustic characteristics . 33
Annex A (normative) Connection box(es) . 36
Annex B (normative) Evaluation of maximum air volume flow and pressure . 38
Annex C (normative) Examples for the evaluation of reference pressure . 39
Annex D (informative) Assessment of part load energy efficiency . 40
Bibliography . 44
European foreword
This document (EN 13141-4:2021) has been prepared by Technical Committee CEN/TC 156 “Ventilation
for buildings”, the secretariat of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by October 2021, and conflicting national standards shall
be withdrawn at the latest by October 2021.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 13141-4:2011.
In addition to a number of editorial revisions, the following main changes have been made with respect
to EN 13141-4:2011:
— the scope has been changed, and concerns now all unidirectional ventilation units (ducted or non-
ducted units, supply or exhaust units), excluding cowls with fans (see EN 13141-5);
— the terms and definitions have been updated in accordance with the parameters used in the
document;
— performance testing of aerodynamic characteristics clause includes new testing of external leakages;
— description of the connection box has been moved in a normative annex;
— determination of the maximum and reference air flow has been added;
— assessment of part load energy efficiency has been moved in an informative annex;
— tests of air flow sensitivity and indoor/outdoor airtightness have been added;
— in the energy part, the characterization of SPI has been added;
— the whole acoustic clause has been reorganized and references to acoustic standard updated;
— testing of noise radiated by the casing for ducted units has been added;
— testing of radiated sound power in the indoor or outdoor space and the airborne sound insulation of
non-ducted units have been added;
— the safety clause has been deleted;
— a new clause dealing with all test results has been created.
A list of all parts in the EN 13141 series, published under the general title Ventilation for buildings —
Performance testing of components/products for residential ventilation can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North
Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.
Introduction
This document specifies methods for the performance testing of components used in residential
ventilation systems to establish the performance characteristics as identified in EN 13142:2021 [1].
This document incorporates many references to other European and International Standards, especially
on characteristics other than the aerodynamic characteristics, for instance on acoustic characteristics.
In most cases, some additional tests or some additional conditions are given for the specific use in
residential ventilation systems.
This document can be used for the following applications:
— laboratory testing;
— attestation purposes.
The position of this document in the field of standards for the mechanical building services is shown in
Figure 1.
Mechanical Building Services
Control systems   Ventilation and air conditioning systems   Heating systems

Air terminal Air handling Mechanical and natural Design criteria for the System
Ductwork     Installation
devices units residential ventilation indoor environment performance

Components/products for
Performance testing and
residential ventilation Performance testing of Simplified calculation Design and dimensioning for
installation checks for
Required and optional components/products for methods for residential residential ventilation
residential ventilation
performance residential ventilation ventilation systems systems
systems
characteristics
Part 1: Externally and internally mounted air transfer devices

Part 2: Exhaust and supply air terminal devices

Part 3: Range hoods for residential use without fan

Part 4: Aerodynamic, electrical power and acoustic performance of unidirectional
ventilation units
Part 5: Cowls, assisted cowls and roof outlet terminal devices

Part 6: Exhaust ventilation system packages used in a single dwelling

Part 7: Performance testing of ducted mechanical supply and exhaust ventilation units
(including heat recovery)
Part 8: Performance testing of non-ducted mechanical supply and exhaust ventilation
units (including heat recovery)

Part 9: Externally mounted humidity controlled air transfer device

Part 10: Humidity controlled extract air terminal device

Part 11: Supply ventilation units

Figure 1 — Position of EN 13141-4 in the field of the mechanical building services
1 Scope
This document specifies aerodynamic, acoustic and electrical power performance test methods for
unidirectional ventilation units used in residential ventilation systems.
This document is applicable to ventilation units:
— installed on a wall or in a window without any duct, A category;
— installed in the upstream of a duct, B category;
— installed in the downstream of a duct, C category;
— installed in a duct, or with duct connection upstream and downstream, D category;
— with one or several inlets/outlets;
— installed in a system with a heat pump for domestic hot water or water for cooling or heating;
— which can be used for supply or exhaust.
This document does not apply to:
— fan assisted cowls which are tested according to EN 13141-5;
— mechanical supply and exhaust units which are tested according to EN 13141-7:2021 or
prEN 13141-8:2021.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 12792, Ventilation for buildings — Symbols, terminology and graphical symbols
EN ISO 717-1, Acoustics — Rating of sound insulation in buildings and of building elements — Part 1:
Airborne sound insulation (ISO 717-1)
EN ISO 5801:2017, Industrial fans — Performance testing using standardized airways (ISO 5801:2017)
EN ISO 5135, Acoustics — Determination of sound power levels of noise from air-terminal devices, air-
terminal units, dampers and valves by measurement in a reverberation room (ISO 5135)
EN ISO 5136, Acoustics — Determination of sound power radiated into a duct by fans and other air-moving
devices — In-duct method (ISO 5136)
EN ISO 10140-1, Acoustics — Laboratory measurement of sound insulation of building elements — Part 1:
Application rules for specific products (ISO 10140-1)
EN ISO 10140-2, Acoustics — Laboratory measurement of sound insulation of building elements — Part 2:
Measurement of airborne sound insulation (ISO 10140-2)
EN ISO 10140-5, Acoustics — Laboratory measurement of sound insulation of building elements — Part 5:
Requirements for test facilities and equipment (ISO 10140-5)
EN ISO 16890 (all parts), Air filters for general ventilation (ISO 16890 (all parts))
ISO 13347-2, Industrial fans — Determination of fan sound power levels under standardized laboratory
conditions — Part 2: Reverberant room method
ISO 13347-3, Industrial fans — Determination of fan sound power levels under standardized laboratory
conditions — Part 3: Enveloping surface methods
ISO 13347-4, Industrial fans — Determination of fan sound power levels under standardized laboratory
conditions — Part 4: Sound intensity method
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 12792, EN ISO 5801:2017 and
the following apply.
ISO and IEC maintain terminological databases for the use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
unit pressure
p
u
pressure increase induced by the ventilation unit given as difference between the total pressures at the
unit outlet and the unit inlet
Note 1 to entry: In case of equal cross-section areas of the inlet and outlet, the total pressure difference is equal
to the static pressure difference.
Note 2 to entry: The parameter p for a ventilation unit is defined as the parameter p described in EN ISO 5801
u f
for a stand alone fan.
3.2
unit static pressure
p
us
pressure increase induced by the ventilation unit given as difference between the static pressure at the
unit outlet and the total pressure at the unit inlet
Note 1 to entry: The parameter p for a ventilation unit is defined as the parameter p described in
us fs
EN ISO 5801 for a stand alone fan.
3.3
external static pressure difference
p
s,ext
pressure increase induced by the ventilation unit given as difference between the static pressures at the
unit outlet and the unit inlet
Note 1 to entry: The external static pressure difference, p , is used to determine the maximum air volume flow
s,ext
and the reference air volume flow.
3.4
maximum air volume flow at zero pressure
q
vmax,0
measured air volume flow corresponding to the maximum achievable fan curve setting of the unit, at 0 Pa
unit static pressure, p
us
3.5
pressure at maximum air volume flow
p
qvmax
external static pressure difference, p , corresponding to the maximum air volume flow
s,ext
3.6
declared maximum air volume flow
q
vmax,d
declared maximum air volume flow of the unit
3.7
maximum air volume flow
q
vmax
air volume flow corresponding to the maximum achievable fan curve setting of the unit at the pressure
p , either declared or measured
qvmax
Note 1 to entry: To determine maximum air volume flow, see 5.2.3.3, Table 5.
3.8
reference air volume flow
q
vref
air volume flow corresponding to the reference pressure
Note 1 to entry: To determine reference air volume flow, see 5.2.3.4, Table 6.
3.9
reference pressure
p
ref
external static pressure difference, p , corresponding to the reference air volume flow
s,ext
3.10
ventilation unit
casing incorporating at least a fan, and that may include duct connections, filters, coils, electrical heating,
or any other air treatment component
3.11
external leakage
q
ve
leakage to or from the air flowing inside the casing of the ventilation unit to or from the surrounding air
3.12
air flow sensitivity
v
maximum relative deviation of the maximum air volume flow q of a non-ducted ventilation unit due
vmax
to a static pressure difference of + 20 Pa and – 20 Pa
3.13
indoor/outdoor airtightness
q
vio
maximum of air volume flow through a non-ducted ventilation unit at static pressure difference of − 20 Pa
and + 20 Pa corresponding to the setting when the fans are “OFF” and all additional shutters are closed
Note 1 to entry: Indoor/outdoor airtightness is not the external leakage.
3.14
non-ducted ventilation units
ventilation unit intended to be used without external ductwork (Cat. A)
3.15
electrical power input
P
E
average overall electrical power input to the equipment within a defined interval of time for standard air
conditions obtained from:
— the power input of the fans;
— controller(s), compressor(s), safety devices of the equipment(s) excluding additional electrical
heating devices not used for defrosting
3.16
electrical power input at the reference air volume flow
P
E,ref
electrical power input at reference air volume flow, q , and reference pressure, p
vref ref
3.17
maximum electrical power input
P
E,max
electrical power input at maximum air volume flow, q , and its corresponding pressure, p
vmax qvmax
4 Symbols and abbreviations
For the purpose of this document, the symbols and abbreviations given in EN 12792 and those listed in
Table 1 apply.
Table 1 — Symbols
Symbol Designation Unit
D airborne sound insulation dB
n,e
D (Ctr) global airborne sound insulation index dB
n,e,w
L sound power level dB
W
L A-weighted sound power level dB(A)
WA
L casing emitted sound dB
Wc
Symbol Designation Unit
L inside emitted sound dB
Wi
L outside emitted sound dB
Wo
p unit pressure Pa
u
p unit static pressure Pa
us
p pressure at maximum air volume flow Pa
qvmax
p reference pressure Pa
ref
p external static pressure difference Pa
s,ext
P electrical power input W
E
P maximum electrical power input W
E,max
P electrical power input at the reference air volume flow W
E,ref
q external leakage 3 a
ve m /s
q indoor/outdoor airtightness 3 a
vio m /s
q maximum air volume flow 3 a
vmax m /s
q maximum air volume flow at zero pressure 3 a
vmax,0 m /s
q declared maximum air volume flow 3 a
vmax,d m /s
q reference air volume flow 3 a
vref m /s
v air flow sensitivity %
— test voltage V
ρ density of ambient air 3
kg/m
a 3
l/s or m /h can be used for measurement of air flow but it shall be verified that all parameters are
consistent with the chosen unit.
5 Performance testing of aerodynamic characteristics
5.1 External leakages
5.1.1 Test installation
The external leakage test shall be carried out by connecting an adjustable fan to the exhaust/supply air
side of the tested ventilation unit as shown in Figure 2.
During the pressurization tests for external leakages, the fan in the unit under test shall be switched off.
The static pressure tapping is located on a blanking off plate and the tap is connected to a pressure
measuring instrument. The external leakage flow rates at over and/or under pressure in the casing are
established with suitable air flow measuring equipment.
The accuracy of the measured values shall be kept within ± 5 % for the flow rates and ± 3 % for the static
pressures of the casing.
Key
1 adjustable fan
2 air flow measuring equipment
3 ventilation unit
4 static pressure measuring equipment
Figure 2 — External leakage test configuration
5.1.2 Test procedure
5.1.2.1 General
External leakages of ventilation units may impact ventilation efficiency of the system if the extract/supply
air flow of the building is not the intended one. The impact will depend on ventilation unit category
according to EN ISO 5801, the location of the unit, inside or outside the building, and the location of the
air flow measurement device during the air flow/pressure test, according to 5.2. Table 2 and Table 3 refer
cases where external leakages shall be reported, and cases where external leakages measurements are
optional because external leakages don't affect building air flows and are already taken into account in
electrical power consumption measurements.
Table 2 — External Leakage for exhaust ventilation unit
External leakage
Category of the
Unit inside the building Unit outside the building
exhaust ventilation
unit, according to
a
Air flow measurement location
EN ISO 5801
Extract side Exhaust side Extract side Exhaust side
Category A (non- Leakage at Leakage at
Optional Optional
ducted) + 250 Pa + 250 Pa
Category B (ducted Leakage at Leakage at
Optional Optional
outlet) + 250 Pa + 250 Pa
Category C (ducted Leakage at Leakage at Leakage at
Optional
inlet) + 250 Pa - 250 Pa - 250 Pa
Category D (both
Leakage Leakage Leakage
ducted inlet and Optional
at ± 250 Pa at ± 250 Pa at ± 250 Pa
outlet)
a
Air flow measurement device location during the air flow/pressure test according to 5.2.
Table 3 — External Leakage for supply ventilation unit
External leakage
Category of the
Unit inside the building Unit outside the building
supply ventilation
unit, according to
Air flow measurement location
EN ISO 5801
Supply side Outdoor side Supply side Outdoor side
Category A (non- Leakage at Leakage at
Optional Optional
ducted) - 250 Pa + 250 Pa
Category B (ducted Leakage at Leakage at Leakage at
Optional
outlet) - 250 Pa + 250 Pa + 250 Pa
Category C (ducted Leakage at Leakage at
Optional Optional
inlet) - 250 Pa + 250 Pa
Category D (both
Leakage Leakage Leakage
ducted inlet and Optional
at ± 250 Pa at ± 250 Pa at ± 250 Pa
outlet)
5.1.2.2 Specificity for units with ducted inlet and/or outlet (Category B, C or D)
At least three different measurement points evenly distributed shall be made between 100 Pa and 300 Pa,
and reported by means of a curve. The external leakage air volume flow rate at 250 Pa shall not be a result
of an extrapolation.
5.1.2.3 Specificity for units with free inlet and outlet (Category A)
For non-ducted units, the external leakage air volume flow, q , shall be measured at over and under-
ve
pressure of 50 Pa. The external leakage at 250 Pa shall then be calculated according to Formula (1).
0,65

qq=
ve,250 ve,50

(1)
5.1.2.4 Result
The external leakage air volume flow q at over and/or under pressure of 250 Pa, shall be reported as
ve
such and also compared to the reference air volume flow q of the unit as a percentage.
vref
5.2 Air flow/pressure performance
5.2.1 General
The test shall be carried out in accordance with EN ISO 5801 and in regards with the specifications given
in 5.2.2 and 5.2.3.
In order to convert the measured values of unit pressure, p , unit static pressure, p , external static
u us
pressure difference, p and electrical power input, P , to the standard conditions (20 °C, 101 325 Pa)
s,ext E
the measured values shall be corrected by the density according to:
— Formula (2), correction of the unit pressure, p ;
u
— Formula (3), correction of the unit static pressure, p ;
us
— Formula (4), correction of the external static pressure difference, p ;
s,ext
— Formula (5), correction of the electrical power input, P .
E
ρ
st
pp⋅
u u,T
e
ρ
T
e
(2)
ρ
st
p p⋅
us us,T
e
ρ
T
e
(3)
ρ
st
pp ⋅
s,ext s,ext,T
e
ρ
T
e
(4)
ρ
st
PP⋅
E E,T
e
ρ
T
e
(5)
=
=
=
=
where
p is the unit pressure under test conditions measured at the density ρ ;
u,T Te
e
p is the unit static pressure under test conditions measured at the density ρ ;
us,T Te
e
p
is the external static pressure difference of the unit under test conditions measured at the
s,ext,T
e
density ρ ;
Te
P is the electrical power input under test conditions measured at the density ρ ;
E,Te Te
ρ
is the density of the ambient air at the test enclosure;
Te
ρ 3
st is the density of 1,2 kg/m corresponding to the air under standard conditions (20 °C and
101 325 Pa).
The simplified calculation method for fans supplying a pressure lower than 2 000 Pa with a Mach number
of less than 0,15 according to EN ISO 5801 can be applied.
5.2.2 Test Installation
5.2.2.1 General
A ventilation unit is specified to supply a given air flow rate to an installation. In order to choose the
appropriate unit, it is necessary to know its aerodynamic performance characteristics, given as the
volume flow rate as a function of unit pressure p or unit static pressure p .
u us
These characteristics are strongly influenced by upstream flow conditions (velocity profile, possible
presence of a swirl and wind). Downstream conditions do not usually affect the unit operation, but the
nature of flow downstream from the unit, especially the swirl, can have an effect on losses in the circuit
and should be taken into account during installation design.
Four categories of installations are defined in EN ISO 5801:
— category A: free inlet and free outlet;
— category B: free inlet and ducted outlet;
— category C: ducted inlet and free outlet;
— category D: ducted inlet and outlet.
For each category, EN ISO 5801 defines the installation in the immediate proximity of the unit, as well as
the position of the pressure measurement.
The test shall be performed according to the intended use of the unit:
— for an extract unit, air flow measurement shall be located at the extract side;
— for a supply unit, air flow measurement shall be located at the supply side.
If the measure can’t be done at the correct side, then:
— if the external leakage, q ≤ 7 % q , then the air volume flow can be measured on the other side
ve vref
of the unit (because the unit can be considered as almost airtight);
— if the external leakage, q > 7 % q , then a correction shall be applied to the results in order to
ve vref
take into account leakages, using the function determined by the three points measurement of
external leakage.
Unidirectional ventilation units which are able to change automatically their direction (alternating units),
can be tested and rated according to this document, for each air directions, if switches ensure that the
test can be proceed with one direction only. For such unit, each air directions shall be tested.
5.2.2.2 Specificity for exhaust or supply ventilation units with multi-inlets or multi-outlets
This type of unit corresponds to a fan mounted in a casing having several inlets or outlets (all ducted) and
only one outlet or inlet which discharges into the open air or into a duct.
These units shall be tested using a category B, C or D installation, but due to the presence of more than
one inlet or outlet, each inlet or outlet shall be connected to the test installation according to the
category B or C. Where for practical reasons (insufficient distance between inlet or outlet ducts placed on
the same side of casing) it is not possible to place two test installations side by side, then apply Annex A.
The test shall be carried out for the maximum configuration: all the inlets or outlets connected.
In case of products that include self-regulating dampers in spigot, the dampers shall be removed in order
to assess the product only. If it is not possible, then the dampers shall be switched in a fixed maximum
opening position (this position can be more or less opened, depending of the technology of regulation).
The presence of the self-regulation dampers during the test and the methodology to fix them in a
maximum opening position shall be described in the test report.
5.2.2.3 Specificity for roof exhaust fans
This type of ventilation unit, normally installed at the downstream end of a duct, shall be tested using a
category C or D installation.
Ventilation units with gravity controlled shutters shall be tested under their correct mounting conditions.
If the discharge can be adjusted (i.e. between vertical and radial), then extreme discharge configurations
shall be tested.
5.2.3 Test procedure
5.2.3.1 General
Where a single value is assigned by the manufacturer as rated voltage, this shall be the test voltage. Where
a voltage range is assigned to the product by the manufacturer that includes 1 ∼ 230 V / 3 ∼ 400 V, the
test voltage shall be 230 VAC.
This voltage shall be maintained to ± 1 % throughout the testing.
The performance characteristics of a unit shall be determined according to the following procedure for
the relevant settings:
a) choose the appropriate installation category according to the intended use of the unit;
b) choose a method for flow rate measurement taking into account in particular the relatively low
pressure supplied by these devices (the use of an auxiliary fan might be necessary);
c) proceed to the test according to EN ISO 5801 using simplified calculation method for fans supplying
a pressure lower than 2 000 Pa with a Mach number of less than 0,15.
5.2.3.2 Determination of external static pressure difference
The relevant pressure parameter determining the maximum air volume flow and reference air volume
flow is the external static pressure difference between unit outlet and unit inlet. It can be measured
directly or derived from the measured unit static pressure curve p considering the installation category
us
according to Table 4.
Table 4 — Determination of the external static pressure difference
External static pressure difference

p
s,ext
Determina- Ducted unit
Non-ducted unit
tion
a a a
Cat A
Cat B Cat C Cat D
Direct
−p p
p −p pp−
3 4
4 3 43
or
measurement
Calculated
based on unit
ρ ρ
2 2
st st
p p p +⋅ v p +⋅ v
us us us 3 us 3
static pressure
2 2
p
us
Calculated
ρ ρ
2 22
st st
based on unit
— p − ⋅ v — p − ⋅ vv−
( )
u4 u 4 3
2 2
pressure p
u
Key
p : Static pressure at inlet side (pressure difference against ambient pressure, in Pa)
p : Static pressure at outlet side (pressure difference against ambient pressure, in Pa)
ρ : Density of 1,2 kg/m corresponding to the air under standard conditions (20 °C, 101 325 Pa)
st
v: Average calculated air flow velocity in the duct, in m/s
a
Duct equipped with pressure tap shall have same section as ventilation unit inlet or outlet (the one
connected). For other section, correction shall applied according to EN ISO 5801.
5.2.3.3 Determination of maximum air volume flow and corresponding pressure
The maximum air volume flow and pressure shall be evaluated on the basis of the measured maximum
achievable air volume flow/pressure curve of the unit according to Table 5 (for example diagrams, see
Annex B).
The maximum air volume flow q shall either be measured or determined by an interpolation
vmax
between the measured points.
Table 5 — Maximum air volume flow and pressure
p
s,ext
p q
Type of unit
qvmax vmax
at 0,7 · q
vmax,0
q
Non-ducted unit (Cat A) — 0 Pa
vmax,0
q at 100 Pa
≥ 100 Pa 100 Pa
v
Ducted unit (Cat B, C, D)
p at 0,7 · q 0,7 · q
< 100 Pa
s,ext vmax,0 vmax,0
NOTE q is limited to 70 % of the maximum air volume flow at zero pressure, q , as minimum in
vmax vmax,0
order to ensure that ducted units are assessed within their characteristic operating range.
If the declared maximum air volume flow q is equal to the measured maximum air volume flow,
vmax,d
in a tolerance of ± MAX(3 m /h ; 10 % q ), then the declared maximum air volume flow shall be used
vmax
as the maximum air volume flow. If not, the measured maximum air volume flow shall be used instead.
5.2.3.4 Determination of reference air volume flow and reference pressure
The reference pressure and reference air volume flow shall be determined from the maximum air volume
flow and corresponding pressure (see 5.2.3.3) and on the basis of measured air volume flow/pressure
curves of the unit, according to Table 6 (for example diagrams, see Annex B). The reference pressure,
p , shall be either measured or determined by an interpolation between the measured points for the
ref
same setting which intends to meet the reference air flow.
Table 6 — Reference air volume flow and reference pressure
Type of unit p p q
s,ext ref vref
at 0,7 · q
vmax,0
Non-ducted unit (CAT A) — 0 Pa a
≥ 0,7 · q
qvmax
≥ 100 Pa c b
≥ 50 Pa 0,7 · q
qvmax
Ducted unit (CAT B, C, D)
< 100 Pa d b
≥ 0,5 · p 0,7 · q
qvmax qvmax
a
The reference air volume flow corresponds to 0,7 · q . If this air flow is not achievable with
vmax
the available settings, then the reference air volume flow corresponds to the air flow at zero pressure
at the next setting that exceeds 0,7 · q (for example diagrams, see Annex C).
vmax
b
For units with constant air flow control, if the reference air volume flow is not achievable at p
ref
with the available settings, then the reference air volume flow corresponds to the air flow at p at
ref
the next setting that exceeds 0,7 · q .
vmax
c
The reference pressure corresponds to 50 Pa. If the reference pressure is not achievable with the
available settings, then the reference pressure corresponds to the pressure at q at the next setting
vref
that exceeds 50 Pa (for example diagrams, see Annex C).
d
The reference pressure corresponds to 0,5 · p . If the reference pressure is not achievable
qvmax
with the available settings, then the reference pressure corresponds to the pressure at q at the
vref
next setting that exceeds 0,5 · p (example diagrams, see Annex C).
qvmax
5.2.3.5 Measurement of air flow/pressure curves for ducted ventilation units
The air volume flow/pressure curves shall be determined according to 5.2.1, 5.2.2 and 5.2.3.1.
Installation categories B, C or D shall be chosen according to the intended use.
A minimum of 3 curves per unit shall be measured and reported for minimum setting, maximum setting
and an intermediate setting. If the ventilation unit has less than 3 settings, then all curves shall be
measured.
A minimum of 8 test points equally distributed shall be measured and reported on each curve.
5.2.3.6 Measurement of air flow for non-ducted ventilation units
The air volume flow shall be determined according to 5.2.2.1, 5.2.3.1 and Figure 3.
Installation category A shall be applied.
Measurements shall be carried out with the maximum fan speed setting at least for the following settings
of external static pressure difference, p :
s,ext
— + 20 Pa;
— - 20 Pa;
— 0 Pa (q ). This point shall not be an interpolation between the two measurements at + 20 Pa and
vmax
− 20 Pa.
For ventilation units with 2 or more settings, the following set points on external static pressure
difference p shall be measured in addition:
s,ext
— 0 Pa with minimum fan speed (q );
vmin
— 0 Pa with an intermediate fan speed (q ) if available, and if possible at 0,7 · q .
vin vmax
Key
p external static pressure difference
s,ext
q maximum air volume flow
vmax
q minimum air volume flow
vmin
q air volume flow at intermediate fan speed setting
vin
dq / dq absolute deviation of maximum air volume flow due to over/under pressure of 20 Pa
v,over v,u
nder
Figure 3 — Air flow measurements (installation category A)
5.3 Air flow sensitiv
...