CEN/TR 15316-6-4:2017

SLOVENSKI STANDARD
01-maj-2018
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Energy performance of buildings - Method for calculation of system energy requirements
and system efficiencies - Part 6-4: Explanation and justification of EN 15316-4-1, Module
M3-8-1, M8-8-1
Heizungsanlagen und Wasserbasierte Kühlanlagen in Gebäuden - Verfahren zur
Berechnung der Energieanforderungen und Nutzungsgrade der Anlagen - Teil 6-4:
Begleitender TR zur EN 15316-4-1 (Wärmeerzeugung für die Raumheizung und
Trinkwarmwasser, Verbrennungssysteme (Heizungskessel, Biomasse))
Performance énergétique des bâtiments - Méthode de calcul des besoins énergétiques
et des rendements des systèmes - Partie 6-4 : Explication et justification de l'EN 15316-4
-1, Module M3-8-1, M8-8-1
Ta slovenski standard je istoveten z: CEN/TR 15316-6-4:2017
ICS:
91.140.10 Sistemi centralnega Central heating systems
ogrevanja
91.140.65 Oprema za ogrevanje vode Water heating equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TR 15316-6-4
TECHNICAL REPORT
RAPPORT TECHNIQUE
April 2017
TECHNISCHER BERICHT
ICS 91.120.10; 91.140.10; 91.140.65
English Version
Energy performance of buildings - Method for calculation
of system energy requirements and system efficiencies -
Part 6-4: Explanation and justification of EN 15316-4-1,
Module M3-8-1, M8-8-1
Performance énergétique des bâtiments - Méthode de Heizungsanlagen und Wasserbasierte Kühlanlagen in
calcul des besoins énergétiques et des rendements des Gebäuden - Verfahren zur Berechnung der
systèmes - Partie 6-4 : Explication et justification de Energieanforderungen und Nutzungsgrade der
l'EN 15316-4-1, Module M3-8-1, M8-8-1 Anlagen - Teil 6-4: Begleitender TR zur EN 15316-4-1
(Wärmeerzeugung für die Raumheizung und
Trinkwarmwasser, Verbrennungssysteme
(Heizungskessel, Biomasse))
This Technical Report was approved by CEN on 27 February 2017. It has been drawn up by the Technical Committee CEN/TC
228.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 15316-6-4:2017 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Introduction . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
3.1 Terms . 7
3.2 Symbols . 7
3.3 Abbreviations and indices . 7
4 Description of the method . 7
4.1 Output of the method . 7
4.1.1 Description . 7
4.1.2 Example . 8
4.2 General description of the method . 9
4.3 Input data . 9
4.3.1 Description . 9
4.3.2 Example . 13
4.4 Boundaries between distribution and generation sub-system . 13
4.5 Default values . 15
4.5.1 Default values for generator efficiency at full load and intermediate load as a
function of the generator power output . 15
4.5.2 Default value for the stand-by heat losses f gen;ls;P0 as a function of the generator power
output . 16
4.5.3 Auxiliary energy . 16
4.6 Product values . 17
4.7 Measured values . 17
4.7.1 Boiler efficiencies from measured values . 17
4.7.2 Measured total thermal losses, power input and calculated gains . 18
4.7.3 Additional default data and calculation for condensing boilers . 18
4.7.4 Thermal losses through the chimney with the burner on at full load fch;on . 20
4.7.5 Thermal losses through the generator envelope fgen;env . 20
4.7.6 Thermal losses through the chimney with the burner off fch;off . 21
4.8 Boiler rated output . 21
5 Generation sub-system basic energy balance . 21
5.1 Heat balance . 21
5.2 Expenditure factor . 22
5.3 Fuel heat input . 23
5.3.1 Description . 23
5.3.2 Example . 23
5.4 Generator auxiliary energy . 24
5.4.1 Description . 24
5.4.2 Example . 24
5.5 Generator losses . 24
5.5.1 Generator loss . 24
5.5.2 Generator thermal loss at specific load ratio βH;gen and power output PPx . 24
5.5.3 Generator thermal loss calculation at full load . 25
5.5.4 Generator thermal loss calculation at intermediate load . 27
5.5.5 Generator thermal loss calculation at 0 % load . 28
5.5.6 Correction factor by additional tests . 29
5.6 Recoverable thermal losses . 29
5.6.1 general . 29
5.6.2 Generator thermal losses through the jacket (generator envelope) . 30
5.6.3 Recoverable thermal losses out of auxiliary energy . 30
5.7 Recovered auxiliary energy . 31
5.7.1 Description . 31
5.7.2 Example . 31
5.8 Auxiliary energy . 32
5.8.1 Description . 32
5.8.2 Example . 32
5.9 Generator thermal output . 33
5.10 Heating time and load factor . 33
5.11 Direct heated DHW heaters . 34
5.11.1 Instantaneous electrical water heater . 34
5.11.2 Instantaneous gas water heater . 34
5.11.3 Gas-fired domestic storage water heaters . 34
5.12 Method for domestic hot water appliance, tested with 24 hours tapping cyclies . 37
Annex A (informative) Additional formulas and default values for parametering the boiler
efficiency method . 39
A.1 Information on the method . 39
A.2 Conversion of the energy content of energy carriers . 45
A.3 Deviation from default values . 45
A.4 Fuel constants for flue gas measurement depending on Siegert constants . 45
A.5 Default values for calculation of thermal losses through the chimney with the burner
off . 47
A.6 Additional default data and calculation for condensing boilers . 48
A.7 Additional default data for generator output and losses . 49
A.8 Additional default data and calculation for water heaters. 49
Annex B (informative) Additional formulas and default values for parametering the boiler
efficiency method . 50
B.1 Information on the method . 50
B.2 Conversion of the energy content of energy carriers . 57
B.3 Deviaton from default values . 57
B.4 Fuel constants for flue gas measurement depending on Siegert constants . 57
B.5 Default values for calculation of thermal losses through the chimney with the burner
off . 59
B.6 Additional default data and calculation for condensing boilers . 59
B.7 Additional default data for generator output and losses . 61
B.8 Additional default data and calculation for water heaters. 62
Annex C (informative) General part default values and information - Boundary condition for
DHW . 63
Bibliography . 64

European foreword
This document (CEN/TR 15316-6-4:2017) has been prepared by Technical Committee CEN/TC 228
“Heating systems and water based cooling systems in buildings”, the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
Introduction
This document informs about EN 15316-4-1 as a part of a series of standards aimed at European
harmonization of the methodology for the calculation of the energy performance of buildings.
A huge amount of informative contents needs indeed to be recorded and made available for users to
properly understand, apply and nationally adapt the EPB standards.
The set of EPB standards, Technical Reports and supporting tools
In order to facilitate the necessary overall consistency and coherence, in terminology, approach,
input/output relations and formats, for the whole set of EPB-standards, the following documents and
tools are available:
a) a document with basic principles to be followed in drafting EPB-standards: CEN/TS 16628:2014,
Energy Performance of Buildings - Basic Principles for the set of EPB standards [1];
b) a document with detailed technical rules to be followed in drafting EPB-standards;
CEN/TS 16629:2014, Energy Performance of Buildings - Detailed Technical Rules for the set of
EPB-standards [2];
c) the detailed technical rules are the basis for the following tools:
1) a common template for each EPB-standard, including specific drafting instructions for the
relevant clauses;
2) a common template for each technical report that accompanies an EPB standard or a cluster of
EPB standards, including specific drafting instructions for the relevant clauses;
3) a common template for the spreadsheet that accompanies each EPB standard, to demonstrate
the correctness of the EPB calculation procedures.
Each EPB-standards follows the basic principles and the detailed technical rules and relates to the
overarching EPB-standard, EN ISO 52000-1 [3].
One of the main purposes of the revision of the EPB-standards is to enable that laws and regulations
directly refer to the EPB-standards and make compliance with them compulsory. This requires that the
set of EPB-standards consists of a systematic, clear, comprehensive and unambiguous set of energy
performance procedures. The number of options provided is kept as low as possible, taking into
account national and regional differences in climate, culture and building tradition, policy and legal
frameworks (subsidiarity principle). For each option, an informative default option is provided
(Annex B).
Rationale behind the EPB Technical Reports
There is a risk that the purpose and limitations of the EPB standards will be misunderstood, unless the
background and context to their contents – and the thinking behind them – is explained in some detail
to readers of the standards. Consequently, various types of informative contents are recorded and made
available for users to properly understand, apply and nationally or regionally implement the EPB
standards.
If this explanation would have been attempted in the standards themselves, the result is likely to be
confusing and cumbersome, especially if the standards are implemented or referenced in national or
regional building codes.
Therefore, each EPB standard is accompanied by an informative technical report, like this one, where all
informative content is collected, to ensure a clear separation between normative and informative
contents (see CEN/TS 16629 [2]):
— to avoid flooding and confusing the actual normative part with informative content;
— to reduce the page count of the actual standard; and
— to facilitate understanding of the set of EPB standards.
This was also one of the main recommendations from the European CENSE project [5] that laid the
foundation for the preparation of the set of EPB standards.
EN 15316-4-1 is intended to replace EN 15316-4-1:2008 and includes Domestic hot water systems,
generation (former EN 15316-3-3) and biomass boilers (former EN 15316-4-7:2008) in this standard
published in 2007-2008 under the mandate M/343 on the EPBD. This revision was required as a result
of the EPBD recast (2010/31/EU).The set of standards developed under mandate M/343 will be revised
to become consistent with the overarching standard under mandate M/480.
The typology method has been removed, the boiler cycling method has been added for existing boilers
to get the input parameters for the case specific boiler efficiency method.
Other generation systems are covered in other sub modules of part M3-8 (see Figure 1).
1 Scope
This Technical Report refers to EN 15316-4-1.
It contains information to support the correct understanding, use and national adaption of standard
EN 15316-4-1.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 89, Gas-fired storage water heaters for the production of domestic hot water
EN 13203-2, Gas-fired domestic appliances producing hot water - Part 2: Assessment of energy
consumption
EN 15316-4-1:2017, Energy performance of buildings - Method for calculation of system energy
requirements and system efficiencies - Part 4-1: Space heating and DHW generation systems, combustion
systems (boilers, biomass), Module M3-8-1, M8-8-1
EN ISO 13790, Energy performance of buildings - Calculation of energy use for space heating and cooling
(ISO 13790)
EN ISO 52000-1:2017, Energy performance of buildings - Overarching EPB assessment - Part 1: General
framework and procedures (ISO 52000-1:2017)
3 Terms and definitions, symbols, abbreviations and indices
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in EN ISO 52000-1:2017 and
EN 15316-4-1:2017 apply.
3.2 Symbols
For the purposes of this document, the symbols and indices given in EN ISO 52000-1:2017 and the
symbols and units given in EN 15316-4-1:2017 apply.
3.3 Abbreviations and indices
For the purposes of this document, the abbreviations and indices given in EN ISO 52000-1:2017 and the
indices given in EN 15316-4-1:2017 apply.
4 Description of the method
4.1 Output of the method
4.1.1 Description
The calculation of the values takes place basically for the zones defined in EN ISO 13790.
If a number of parts of systems are contained in the various process domains then the values are to be
added together for further analysis.
Here it is to be taken into account that the heating data are to be related to the gross calorific value.
In the following sections the thermal and auxiliary energy components of the different process domains
are determined for further analysis in ISO/CD 11368.
For output quantities, see Table 1.
Table 1 — Output quantities
Calculation
clause of Validity Destination
Description Symbol Unit Varying
EN 15316-4- interval module
1:2017
Fuel heat input E kWh see 6.3 0…∞ M 3–1 YES
gen;in
Recoverable generation heat losses for
heating system (in the calculation Q kWh see 6.6 0…∞ M 3–1 YES
gen;ls;rbl
interval)
generation heat losses (in the calculation
Q kWh see 6.5 0…∞ M 3–1 YES
gen;ls;
interval)
Expenditure factor of the generator for
εgen - see 6.2 1 - 10 M 3–1 YES
the whole service
Expenditure factor of the generator for
εH;gen - see 6.2 2 - 10 M 3–1 YES
heating
Expenditure factor of the generator for
ε - see 6.2 3 - 10 M 3–1 YES
C;gen
cooling
Expenditure factor of the generator for
ε - see 6.2 4 - 10 M 3–1 YES
V;gen
ventilation
Expenditure factor of the generator for
ε - see 6.2 5 - 10 M 3–1 YES
W;gen
DHW
heat generation auxiliary energy for the
heating system (in the calculation W kWh see 6.4 0…∞ M 3–1 YES
gen,
interval)
Fuel type  List  not relevant M 3–1 NO
4.1.2 Example
Table 2 — Example for output quantities
Description Symbol Value
Fuel heat requirement Egen;in 99 443 kWh = 357,995 GJ
Recoverable heat loss Qgen;ls;rbl 408 kWh = 1,468 GJ
Total generation heat loss Q 1 574 kWh = 5,667 GJ
gen;ls
Auxiliary consumption Wgen 524,34 kWh = 1,888 GJ
expenditure factor of the generator

for the whole service ε 0,99
gen
for heating εH;gen 0,99
ε
C;gen
for cooling 0,00
εV;gen
for ventilation 0,00
for DHW εW;gen 0,00
4.2 General description of the method
The calculation method of the generation sub-system takes into account heat losses and/or recovery
due to the following physical factors:
— heat losses to the chimney (or flue gas exhaust) and the generator(s) during total time of generator
operation (running and stand-by);
— auxiliary energy.
The calculation is independent from the time steps.
There are a basic calculation for
— boilers at all (EN 15316-4-1:2017, Clause 6.);
— direct heated domestic hot water heaters (EN 15316-4-1:2017, 6.11) and
— domestic hot water appliance tested with 24 h tapping cycles (EN 15316-4-1:2017, 6.12).
There are three possible inputs for the generation efficiency calculation:
— default values (EN 15316-4-1:2017, 5.5);
— product values (EN 15316-4-1:2017, 5.6);
— measured values (EN 15316-4-1:2017, 5.7).
Default values are given in Annex B.
Product values by the manufactures should be tested according to the appropriated European Standard
(see Bibliography).
Measured values are for existing boilers, condensing boilers and on-site inspection (see 5.6).
Here it is to be taken into account that the heating data are to be related to the gross calorific value.
4.3 Input data
4.3.1 Description
Input quantities from other parts of the heating system standards, see Table 3.
Table 3 — Input quantities
Validity Destination
Description Symbol Unit Varying
interval module
Fuel type GEN_FUEL List not relevant M 3–4, M 8–4 NO
Generator Type GEN_TYP List not relevant M 3–4, M 8–4 NO
Burner type GEN_BURN List not relevant M 3–4, M 8–4 NO
Boiler location TH_ZONE List not relevant M 3–4, M 8–4 NO
HEAT_GEN_CT
M 3–4, M 8–4
Type of control RL List not relevant NO
GEN_CIRC_TYP
M 3–4, M 8–4
Generation circuit typology OL List not relevant NO
number of dwellings within a building N - 0…∞ M 3–1 YES
flat
number of peak tappings per day nSp - 0…∞ M 3–1 YES
Heat load Φ kW 0…∞ M 3–3 YES
h
Rated output for cooling system Pn,C kW 0…∞ M 4–3 YES
Rated output for ventilation system P kW 0…∞ M 5–3 YES
n,V
Rated output for DHW system Pn,W kW 0…∞ M 8–3 YES
Heat input to the heating distribution
M 3–6,
system (in the respective time) QH,dis;in kWh 0…∞ Yes
Heat input to the cooling distribution
M 4–6
system (in the respective time) Q kWh 0…∞ YES
C,dis;in
Heat input to the ventilation distribution
M 5–6,
system (in the respective time) Q kWh 0…∞ YES
V,dis;in
daily energy need for domestic hot water, QW,b,d kWh 0…∞ M 8–6 YES
Heat input to the domestic hot water
distribution system (in the respective M 8–6
time) QW,dis;in kWh 0…∞ YES
Usage period for heating (in the
M 3–4, M 8–4
calculation interval), tH;use h or d 0…8760 YES
Usage period for cooling (in the
M 4–4
calculation interval) t h or d 0…8760 YES
C;use
Usage period for ventilation (in the
M 5–4
calculation interval) t h or d 0…8760 YES
V;use
Usage period for domestic hot water (in
M 8–4
the calculation interval) tW;use h or d 0…8760 YES
Running time for heating (in the s/h or M 3–4, M 8–4,
calculation interval) tH h/mth 0…3600 EN ISO 13790 YES
Running time for cooling system – when s/h or
M 3–4, M 8–4
connected tC h/mth 0…3600 YES
Running time for ventilation system – s/h or
M 3–4, M 8–4
when connected t h/mth 0…3600 YES
V
Running time for DHW system – when s/h or
M 3–4, M 8–4
connected t h/mth 0…3600 YES
W
Validity Destination
Description Symbol Unit Varying
interval module
see external climate
External air temperature ϑe °C −30 . . +30 data, M 3–4, M 8–4 YES
see external climate
Daily average design temperature ϑ °C −30 . . +31 data, M 3–4, M 8–5 YES
e;min
Generator average water temperature (or
return temperature to the generator for
M 3–4, M 8–4
condensing boilers) as a function of the
specific operating conditions ϑHc;mn °C 0 . . 110 YES
Average return temperature to the
generator for condensing boilers as a
M 3–4, M 8–4
function of the specific operating
conditions ϑ °C 0 . . 110 YES
Hc;RT
Generator average water temperature as
a function of the specific operating
M 3–4, M 8–4
conditions for cooling systems - when
connected ϑCc;mn °C 0 . . 110 YES
Generator average water temperature as
a function of the specific operating
M 3–4, M 8–4
conditions for ventilation systems - when
connected ϑVc;mn °C 0 . . 110 YES
Generator average water temperature as
a function of the specific operating
M 3–4, M 8–4
conditions for DHW systems - when
connected ϑ °C 0 . . 110 YES
Wc;mn
Average return temperature to the
generator for condensing boilers as a
function of the specific operating M 3–4, M 8–4
conditions for cooling systems - when
connected ϑCc;RT °C 0 . . 110 YES
Average return temperature to the
generator for condensing boilers as a
function of the specific operating M 3–4, M 8–4
conditions for ventilation systems - when
connected ϑ °C 0 . . 110 YES
Vc;RT
Average return temperature to the
generator for condensing boilers as a
function of the specific operating M 3–4, M 8–4
conditions for DHW systems - when
connected ϑ °C 0 . . 110 YES
Wc;RT
Average return temperature to the
ϑgen;RT °C −30 . . +30 measured YES
generator for condensing boilers
Ambient temperature ϑ °C −30 . . +31 M 3–4, M 8–4 YES
brm
Cold water temperature ϑk °C 0 . . 95 M 3–4 YES
Delivered energy input of the generation
sub-system (measured fuel input) (in the Egen;del;in kg, m 0…∞ M 3–1 YES
calculation interval)
Validity Destination
Description Symbol Unit Varying
interval module
Generator output at full load Pn kW 0…∞ M 3–2 YES
Generator output at intermidiate load Pint kW 0…∞ M 3–3 YES
Temperature difference between boiler
return water temperature and flue gas Δϑwfg °C −30 . . +30 measured YES
temperature at part load
see external climate
External air temperature ϑe °C −30 . . +30 YES
data, M 3–4, M 8–4
see external climate
Ambient temperature ϑbrm °C −30 . . +31 YES
data, M 3–4, M 8–5
Out of additional tests
Full load efficiency with mean water
ηPn;add - 0 . . 1 measured YES
temperature ϑgen;test;Pn;add
ϑgen;test;Pn;a
Mean water temperature at full load °C −30 . . +30 measured YES
dd
Part load efficiency with mean water
ηPint;add - 0 . . 1 measured YES
temperature ϑgen;test;Pint;add
ϑgen;test;Pint;
Mean water temperature at part load °C −30 . . +31 measured YES
add
The daily operation is taken into account by the heating time (operating hours/period of duration) t .
H,op
The assumption is made that there is always only one user. Where there are a number of different loads
a differentiation shall be made between the individual requirements for each case.
Only if the useful heat demand QH;dis;in > 1 kWh (in the calculation interval) is heating necessary.
If the generator provides heat for heating, cooling, ventilation and domestic hot water, the index H shall
be replaced by C, V or W. In the following only H is used for simplicity.
4.3.2 Example
Table 4 — Example of input quantities
Description Symbol Value
Boiler type  Gas Condensing boiler 2005
Nominal power (heat output) Pn 70 kW
Fuel used.  Natural gas
Burner type  Modulating, fan assisted
Boiler location  Boiler room
Type of control  Depending on outside temperature
Generation circuit typology  Direct connection of boiler
Generator heat output QH;gen;out 353 GJ = 98 000 kWh
Usage period for heating t 160 d = 3 840 h
H,use
Generation average temperature ϑ 48,9 °C
Hc;mn
Generation return temperature ϑHc;RT 37,7 °C
load factor at full load β β = 1,0 (single boiler, only heating load)
Pn
Pn
β
load factor at intermediate load βPint = 0,3 (single boiler, only heating load)
Pint
4.4 Boundaries between distribution and generation sub-system
Boundaries between generation sub-system and distribution sub-system should be defined according to
the following principles.
If the generation-subsystem includes the generator only (i.e. there is no pump within the generator), the
boundary with the distribution sub-system is represented by the hydraulic connection of the boiler, as
shown in Figure 1.
Key
gen generation subsystem
dis distribution subsystem
em emission subsystem
Figure 1 — Sample subsystems boundaries
A pump physically within the boiler is however considered part of the distribution sub-system if it
contributes to the flow of heating medium to the emitters. An example is shown in Figure 2.

Key
gen generation subsystem
dis distribution subsystem
em emission subsystem
Figure 2 — Sample subsystems boundaries
Only pumps dedicated to generator requirements may be considered within the generation sub-system.
An example is shown in Figure 3.

Key
gen generation subsystem
dis distribution subsystem
em emission subsystem
Figure 3 — Sample subsystems boundaries
4.5 Default values
4.5.1 Default values for generator efficiency at full load and intermediate load as a function of
the generator power output
4.5.1.1 Description
The generator efficiency at full load and intermediate load as a function of the generator power output
is calculated with Formula (1):
cc+⋅ logP
12 n
η = (1)
gen;Pn
For condensing boiler the generator efficiency at full load shall be elaborated between 60 °C and 30 °C
return temperature using Formula (2) for 60 °C and Formula (3) for 30 °C:
cc+⋅ logP
12 n
η = (2)
gen;Pn;60
cc+⋅ logP
12 n
η = (3)
gen;Pn;30
The generator efficiency at intermediate load as a function of the generator power output is calculated
with Formula (4):
cc+⋅ logP
34 n
η = (4)
gen;Pint
where
P is the nominal power output, in kW limited to a maximum value of 400 kW. If the
n
nominal power output of the generator is higher than 400 kW, then the value of
400 kW is to take;
c , c , c , c are the coefficients given in Tables A.1 and A.2 and Tables B.1 and B.2.
1 2 3 4
4.5.1.2 Example
Gas condensing boiler 2005 with nominal power P = 70 kW.
n
Table 5 — Parameters for calculation of generator efficiency and temperature limitation
Boiler Build Factor c Factor c Factor Factor c ϑ ϑ
1 2 4 gen;test;Pn gen;test;Pint
type year c
°C °C
Condensing
boiler,
improved
from 1999 oil/gas 94,0 1,0 103 1,0 60 30
gas 102,0 1,0   30
94 +⋅1,0 log70
η = = 95,85 %
gen;Pn;60
102 +⋅1,0 log70
η = = 103,85 %
gen;Pn;30
103 +⋅1,0 log70
η = = 104,85 %
gen;Pint
4.5.2 Default value for the stand-by heat losses f as a function of the generator power
gen;ls;P0
output
4.5.2.1 Description
f is calculated with Formula (5):
gen;ls;P0
c
cP⋅
( )
5 n
f = (5)
gen;ls;P0
where
P is the nominal power output, in kW;
n
c , c are the parameters given in Table A.3 and Table B.3.
5 6
4.5.2.2 Example
Table 6 — Excerpt of Table Parameters for calculation of power consumption of auxiliary
equipment
Boiler type Build year Factor c Factor c ϑ
5 6 gen;test;P0
Condensing boilers
°C
(oil/gas)
after 1994 4,0 –0,4 70
−04,
4,0 ⋅ 70
( )
f = = 0, 73 %
gen;ls;P0
4.5.3 Auxiliary energy
4.5.3.1 Description
Default value for the power consumption of auxiliary equipment is calculated with Formula (6):
n
cc+⋅ P
( )
7 8 n
P = (6)
aux;Px
1 000
where
P is the nominal power output, in kW;
n
c , c , n are the parameters given in Table A.6 and Table B.6.
7 8
4.5.3.2 Example
Table 7 — Example of auxiliary energy
boiler type load c c n
7 8
W W
P 0 45 0,48
n
condensing boiler (oil/gas) P 0 15 0,48
int
b
P 15 0 0
0,48
0,0 +⋅45 70
( )
P = = 0,345 8 kW
aux;Pn
1 000
0,48
0,0 +⋅15 70
( )
P = = 0,115 3 kW
aux;Pint
1 000
15 +⋅0 70
( )
P = = 0,015 kW
aux;P0
1 000
4.6 Product values
Product values by the manufactures shall be tested according to the appropriated European Standard
(see Bibliography).
4.7 Measured values
4.7.1 Boiler efficiencies from measured values
The efficiency of the boiler at full load η is calculated with Formula (7):
gen;Pn
PP−− P
gen;del gen;;ls ch;on gen;;ls env
η = (7)
gen;Pn
P
gen;del
The efficiency of the boiler at part load η is calculated with Formula (8):
gen;Pint
P ⋅ β − β ⋅ P − PP+ + 1 − β ⋅ P + P
( ) ( ) ( )
( )
gen;del Pint Pint gen;;ls ch;on cond gen;;ls env Pint gen;;ls ch;off gen;;ls env
η =
gen;Pint
P ⋅ β
gen;del Pint
(8)
For condensing boiler P is needed (see Formula (24)) otherwise P = 0.
cond cond
The values for stand by heat losses are calculated with Formula (9):
f ff+ (9)
gen;ls;P0 ch;;off gen env
=
4.7.2 Measured total thermal losses, power input and calculated gains
Thermal losses through the chimney with the burner on P are given with Formula (10):
gen;ls;ch;on
f
ch;on
PP⋅ (10)
gen;ls;ch;on gen;del
Thermal losses through the chimney with the burner off Pgen;ls;ch;off are given with Formula (11):
f
ch;off
PP⋅ (11)
gen;ls;ch;off gen;del
Thermal losses through the generator envelope P are given with Formula (12):
gen;ls;env
P fP⋅ (12)
gen;ls;env gen;;env gen del
The calculation procedure for condensation at part load is calculated in EN 15316-4-1:2017, 5.7.3.
The average power input to the generator P in kW is calculated depending on the energy carrier
gen;del
using Formula (13)
 
kWh
PE ⋅ H (13)
 
gen;del gen;;del in i
3600kJ
 
And the nominal power of the boiler P is calculated with Formula (14)
n
PPη ⋅ (14)
n gen;;Pn gen del
4.7.3 Additional default data and calculation for condensing boilers
The specifications of the gas volumes based on ISO 8778.
Flue gas temperature (at boiler outlet connection to flue gas), if not measured, is calculated with
Formula (15):
ϑ ϑ +∆ϑ (15)
fg gen;RT wfg
where
ϑ is the boiler return water temperature during burner running .
gen;RT
The return temperature for part load measurement is 30 °C. The temperature difference Δϑ between
wfg
boiler return water temperature and flue gas temperature at part load normally is 10 K.
3 3 3
Actual amount of dry flue gas V in m /m or m /kg is calculated with Formula (16):
fg;dry
VV ⋅ (16)
fg;dry fg;st;dry
21 − x
O2;fg;dry
3 3 3
Actual amount of dry combustion air V in m / m or m /kg is calculated with Formula (17):
air;dry
V V +−V V (17)
air;dry air;st;dry fg;dry fg;st;dry
NOTE 1 V −V is excess air.
fg;dry fg;st;dry
Combustion air temperature ϑ is assumed either equal to installation room temperature for type B
brm
appliances or to external air temperature for type C appliances.
=
=
=
=
=
=
=
=
Saturation humidity of air m and flue gas m shall be calculated according to ϑ
H2O;air;sat H2O;fg;sat brm
(combustion air temperature) and ϑ (flue gas temperature) respectively and expressed as kg of
fg
humidity per m of dry air or dry flue gas. Data can be found in Table A.12 and Table B.12. Linear or
polynomial interpolation shall be used for intermediate temperatures.
Total humidity of combustion air m in kg/ m or kg/kg is calculated with Formula (18):
H2O;air
x
air
mm ⋅⋅V (18)
H2O;air H2O;air;sat air;dry
where
x is the combustion air relative humidity. Default value is given in Table A.15 and Table B.15.
air
Total humidity of flue gas m in kg/m or kg/kg is calculated with Formula (19):
H2O;fg
x
fg
mm ⋅ V⋅ (19)
H2O;fg H2O;fg;sat fg;dry
where
x is the flue gas relative humidity. Default value is given Table A.15 and Table B.15.
fg
The amount of condensing water m in kg/ m or kg/kg is calculated with Formula (20):
H2O;cond
(20)
m =m +−m m
H2O;cond H2O;st H2O;air H2O;fg
If m is negative, there is no condensation. Then m = 0 and f = 0.
H2O;cond H2O;cond cond
The specific latent heat of condensation h in kJ/kg is calculated with Formula (21) or Formula (22):
cond;fg
hC2500,6 kJ/kg-ϑ *,2 435kJ/kg *° (21)
cond;fg fg
or
(22)
hC694,61 Wh/kg-ϑ *,0 676 4 Wh/kg *°
cond;fg fg
NOTE 2 Use Formula (22) or (23) according to the choice of units for energy and time.
The specific condensation heat Q in kJ/kg or kJ/m is calculated with Formula (23):
cond
Qm= * h (23)
cond H2O;cond cond;fg
The calculation is based on gross calorific values to get positive values, so the recovered latent heat of
condensation P is calculated with Formula (24):
cond
Q
cond
PP⋅ (24)
cond gen;del
H
s
where
H is the gross calorific value (see A.13 and B.13)
s
=
=
=
=
=
4.7.4 Thermal losses through the chimney with the burner on at full load f
ch;on
Thermal losses through the chimney with the burner on f can be calculated according to the flue gas
ch;on
analysis results (Formula (25)):
measuring O2

c

f =ϑϑ−⋅ + c (25)
( )
ch;;on meas fg int;brm 11

21% − X
O
2
The constants c and c are given in Table A.10 and Table B.10.
10 11
The measured value shall be corrected to reference conditions according to water temperature using
the Formula (26):
 
ff −−ϑ ϑ ⋅ f (26)
( )
ch;on ch;on;meas gen;ref gen;meas corr;ch;on
 
 
where
f are the measured losses through the chimney with burner on.
ch;on;meas
ϑ is the reference average water temperature in the boiler at test conditions
gen;ref
(average of flow and return temperature, usually flow temperature 80 °C, return
temperature 60 °C).
ϑgen;meas is the average water temperature in the boiler – or for condensing boiler return
temperature corresponding to ϑ = 60 °C - during measurement of f .
gen;ref ch;on;meas
f is the correction factor for fch;on.
corr;ch;on
Default values for f = 0,045 [%/°C].
corr;ch;on
4.7.5 Thermal losses through the generator envelope f
gen;env
If there is no measurement possible the part of stand-by heat losses attributed to heat losses through
the generator envelope is given by
...