SIST EN 13203-1:2025

SLOVENSKI STANDARD
01-september-2025
Nadomešča:
SIST EN 13203-1:2015
Plinske gospodinjske naprave za pripravo tople sanitarne vode - 1. del:
Ocenjevanje zmogljivosti priprave tople vode
Gas fired domestic appliances producing hot water - Part 1: Assessment of performance
of hot water deliveries
Gasbeheizte Geräte für die sanitäre Warmwasserbereitung für den Hausgebrauch - Teil
1: Bewertung der Leistung der Warmwasserbereitung
Appareils domestiques produisant de l'eau chaude sanitaire utilisant les combustibles
gazeux - Partie 1 : Évaluation de la performance en puisage d'eau chaude
Ta slovenski standard je istoveten z: EN 13203-1:2025
ICS:
91.140.65 Oprema za ogrevanje vode Water heating equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 13203-1
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2025
EUROPÄISCHE NORM
ICS 91.140.65 Supersedes EN 13203-1:2015
English Version
Gas fired domestic appliances producing hot water - Part
1: Assessment of performance of hot water deliveries
Appareils domestiques produisant de l'eau chaude Gasbeheizte Geräte für die sanitäre
sanitaire utilisant les combustibles gazeux - Partie 1 : Warmwasserbereitung für den Hausgebrauch - Teil 1:
Évaluation de la performance en puisage d'eau chaude Bewertung der Leistung der Warmwasserbereitung
This European Standard was approved by CEN on 4 May 2025.

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, Türkiye 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
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 13203-1:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 General test conditions . 7
4.1 Reference conditions . 7
4.2 Measurement uncertainties . 7
4.3 Test conditions . 8
4.3.1 General . 8
4.3.2 Test room . 8
4.3.3 Water supply . 8
4.3.4 Steady-state . 8
4.3.5 Initial adjustment of the appliance . 8
4.3.6 Initial state conditions . 9
4.3.7 Electrical supply . 9
5 Characterization of the domestic hot water function of appliances . 9
5.1 General . 9
5.2 Characterization according to the domestic hot water flow rates . 9
5.2.1 Specific flow rate . 9
5.2.2 Tapping capability . 10
5.2.3 Classification according to the quantity of available domestic hot water . 11
5.3 Classification according to the quality of the domestic hot water produced . 12
5.3.1 Classification procedure . 12
5.3.2 Test for classification according to the performance in delivery of domestic hot
water production . 13
6 Information . 16
7 Calculation of V40 - Mixed water at 40 °C (V40) . 16
Annex A (informative)  Test conditions . 17
Annex B (informative)  Test rig and measurement devices . 30
B.1 General . 30
B.2 Pressure measurement . 31
B.3 Temperature measurement . 31
Annex ZA (informative) Relationship between this European Standard and the ecodesign
requirements of Commission Regulation (EU) n° 814/2013 [OJEU L239 of 6
September 2013] aimed to be covered . 34
Bibliography . 35

European foreword
This document (EN 13203-1:2025) has been prepared by Technical Committee CEN/TC 109 “Central
heating boilers using gaseous fuels”, the secretariat of which is held by NEN.
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 December 2025, and conflicting national standards shall
be withdrawn at the latest by December 2025.
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 13203-1:2015.
The changes in this revision were oriented to align, when relevant, the requirements and tests between
instantaneous appliance and appliances with a storage tank. The main changes are the following:
— editorial improvement (definitions, tapping capacity, …);
— alignment of some Figures with the revised text;
— reference conditions (4.1) aligned to EN 13203-2:2022;
— tests for classification of the appliance on domestic water production (5.3.2 - classification, 5.3.2.7 –
temperature fluctuation).
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
For the relationship with EU Legislation, see informative Annex ZA, which is an integral part of this
document.
NOTE Useful standards are EN 26, EN 15502-1, EN 15502-2-1 and EN 15502-2-2 (see the Bibliography).
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies 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, Türkiye and the United Kingdom.
1 Scope
This document is applicable to gas-fired appliances producing domestic hot water. It applies to both
instantaneous and storage appliances; water-heaters and combination boilers that have:
— heat input not exceeding 70 kW; and
— hot water storage capacity (if any) not exceeding 500 l.
A combination boiler can be fitted with a storage tank or not. The domestic hot water production can be
integrated or coupled. The product is considered as a single appliance.
This document specifies in qualitative and quantitative terms the performance in delivery of domestic
hot water for a selected variety of uses. It also gives a system for presenting the information to the user.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— IEC Electropedia: available at https://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp/
3.1
control cycle
time cycle for keeping components and/or the hot storage water tank (if any) of the domestic hot water
circuit at predetermined temperature level, consists of an «ON» duration time during which the heating
of the domestic hot water (by gas energy and electric auxiliary energy) is operating, and an «OFF»
duration time during which no heating occurs
3.2
domestic water mean temperature (T )
m
average temperature of the water delivered during the time Δt
T ∫T ×dt
m
∆t
3.3
domestic water test temperature
temperature of the delivered water at which the tests are conducted
3.4
storage tank
reservoir for domestic hot water
=
3.5
kitchen specific flow rate (D )
c
domestic hot water flow rate corresponding to a mean temperature rise of 45 K that the appliance can
supply
Note 1 to entry: Dc is expressed in litre per minute (l/min).
3.6
minimum declared water flow rate (D )
m
lowest domestic hot water flow rate stated by the manufacturer maintaining a stable temperature
Note 1 to entry: D is expressed in litre per minute (l/min).
m
3.7
nominal domestic hot water heat input (Q )
nw
value of the heat input stated by the manufacturer for the production of domestic hot water
Note 1 to entry: Qnw is expressed in kilowatt (kW).
3.8
overall performance factor (F)
numerical value used to quantify the overall performance associated with domestic hot water use,
corresponding to the sum of the products of the particular performance factors multiplied by the
weighting coefficients
n
F af ×
∑
ii
i=1
3.9
particular performance factor (f )
i
numerical value which quantifies each of the performance criteria
Note 1 to entry: each performance criteria are listed in Table 1
3.10
specific flow rate (D)
domestic hot water flow rate declared by the manufacturer corresponding to a mean temperature rise of
30 K that the appliance can supply in two successive delivery periods
Note 1 to entry: D is expressed in litre per minute (l/min).
3.11
summer mode
conditions during which the appliance supplies energy only for the production of domestic hot water
3.12
tapping capability (R)
hot water delivery flow rate, as stated by the technical documentation, at which water can be drawn off
for a specified time or times with a predetermined temperature rise
Note 1 to entry: the specified times can be 5 min; 10 min; 20 min or continuous.
Note 2 to entry: R is expressed in litre per minute (l/min).
=
3.13
temperature fluctuation at a constant water flow rate (ΔT )
difference between the
...