SIST EN 12897:2016+A1:2020

Water supply - Specification for indirectly heated unvented (closed) storage water heaters

EN 12897:2016+A1 specifies the constructional and performance requirements and methods of test for indirectly heated, unvented (closed) storage water heaters of up to 2 000 l volume suitable for connection to a water supply at a pressure between 0,05 MPa and 1,0 MPa (0,5 bar and 10 bar), and fitted with control and safety devices designed to prevent the temperature of the stored drinking water from reaching 95 °C. Whilst storage water heaters intended primarily for direct heating are not covered by this document, it does allow the provision of electric heating elements for auxiliary use.

Wasserversorgung - Bestimmung für mittelbar beheizte, unbelüftete (geschlossene) Speicher-Wassererwärmer

Dieses Dokument legt die Anforderungen an die Konstruktionstechnik und die Leistung und Prüfverfahren für mittelbar (indirekte) beheizte, unbelüftete (geschlossene) Speicher Wassererwärmer bis zu 2 000 l Volumen fest, die für den Anschluss an ein Wasserversorgungssystem bei einem Druck zwischen 0,05 MPa und 1,0 MPa (0,5 bar und 10 bar) geeignet und mit Regel  und Sicherheitseinrichtungen ausgerüstet sind, die so ausgelegt sind, dass die Temperatur des gespeicherten Trinkwassers 95 °C nicht übersteigt.
Obwohl dieses Dokument keine Speicher Wassererwärmer behandelt, die hauptsächlich für direkte Er-wärmung vorgesehen sind, lässt es die Bereitstellung von elektrischen Heizelementen zu Hilfszwecken zu.

Alimentation en eau - Prescriptions pour préparateurs d'eau chaude par accumulation à chauffage indirect non ouverts à l'air libre (fermés)

Oskrba z vodo - Specifikacija za posredno ogrevane neprezračevane (zaprte) akumulacijske grelnike vode

General Information

• Status: Published
• Publication Date: 10-Mar-2020
• ICS: 91.140.65 - Water heating equipment
• Technical Committee: IOVO - Water supply and waste water engineering
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 17-Feb-2020
• Due Date: 23-Apr-2020
• Completion Date: 11-Mar-2020
• Directive: 812/2013 - Commission Delegated Regulation (EU) No 812/2013 of 18 February 2013 supplementing Directive 2010/30/EU of the European Parliament and of the Council with regard to the energy labelling of water heaters, hot water storage tanks and packages of water heater and solar device
• Directive: 814/2013 - Commission Regulation (EU) No 814/2013 of 2 August 2013 implementing Directive 2009/125/EC of the European Parliament and of the Council with regard to ecodesign requirements for water heaters and hot water storage tanks
• Mandate: M/534 - [C(2015)2625] Standardisation request to the European standardisation organisations pursuant to Article 10(1) of Regulation (EU) No 1025/2012 of the European Parliament and of the Council in support of implementation of Commission Regulation (EU) No 814/2013 of 2 August 2013 implementing Directive 2009/125/EC of the European Parliament and of the Council with regard to ecodesign requirements for water heaters and hot water storage tanks and Commission Delegated Regulation (EU) No 812/2013 of 18 February 2013 supplementing Directive 2010/30/EU of the European Parliament and of the Council with regard to the energy labelling of water heaters, hot water storage tanks and packages of water heater and solar device
• Ref Project: EN 12897:2016+A1:2020 - Water supply - Specification for indirectly heated unvented (closed) storage water heaters

Relations

• Replaces: SIST EN 12897:2016 - Water supply - Specification for indirectly heated unvented (closed) storage water heaters
• Effective Date: 01-Apr-2020
• Consolidates: SIST EN 12897:2016 - Water supply - Specification for indirectly heated unvented (closed) storage water heaters
• Effective Date: 18-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 12897:2016+A1:2020
01-april-2020
Nadomešča:
SIST EN 12897:2016
Oskrba z vodo - Specifikacija za posredno ogrevane neprezračevane (zaprte)
akumulacijske grelnike vode

Water supply - Specification for indirectly heated unvented (closed) storage water

heaters
Wasserversorgung - Bestimmung für mittelbar beheizte, unbelüftete (geschlossene)
Speicher-Wassererwärmer

Alimentation en eau - Prescriptions pour préparateurs d'eau chaude par accumulation à

chauffage indirect non ouverts à l'air libre (fermés)
Ta slovenski standard je istoveten z: EN 12897:2016+A1:2020
ICS:
91.140.65 Oprema za ogrevanje vode Water heating equipment
SIST EN 12897:2016+A1:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 12897:2016+A1:2020
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2020
EUROPÄISCHE NORM
ICS 91.140.65
English Version
Water supply - Specification for indirectly heated
unvented (closed) storage water heaters

Alimentation en eau - Prescriptions pour préparateurs Wasserversorgung - Bestimmung für mittelbar

d'eau chaude par accumulation à chauffage indirect beheizte, unbelüftete (geschlossene) Speicher-

non ouverts à l'air libre (fermés) Wassererwärmer

This amendment A1 modifies the European Standard EN 12897:2016; it was approved by CEN on 9 October 2019.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of

this amendment into the relevant 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 amendment 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

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12897:2016+A1:2020 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 4

Introduction .................................................................................................................................................................... 5

1 Scope .................................................................................................................................................................... 6

2 Normative references .................................................................................................................................... 6

3 Terms, definitions and symbols ................................................................................................................. 7

3.1 Terms and definitions ................................................................................................................................... 7

3.2 Symbols ............................................................................................................................................................... 8

4 Requirements ................................................................................................................................................... 8

4.1 Constructional requirements ..................................................................................................................... 8

4.1.1 Inspection access ............................................................................................................................................. 8

4.1.2 Draining .............................................................................................................................................................. 8

4.1.3 Hydraulic connections ................................................................................................................................... 8

4.2 Temperature control ..................................................................................................................................... 9

4.3 Mechanical resistance and stability ......................................................................................................... 9

4.3.1 Pressure resistance of water storage vessel ......................................................................................... 9

4.3.2 Pressure resistance of primary heater.................................................................................................... 9

4.3.3 Durability ........................................................................................................................................................... 9

4.3.4 Leakage test on double-walled primary heater ................................................................................ 11

4.4 Safety equipment.......................................................................................................................................... 11

4.4.1 General ............................................................................................................................................................. 11

4.4.2 Energy cut-out device ................................................................................................................................. 11

4.4.3 Temperature relief valve .......................................................................................................................... 11

4.4.4 Pressure relief/expansion valve ............................................................................................................ 11

4.4.5 Pressure reducing valve ............................................................................................................................ 11

4.4.6 Provision for expansion ............................................................................................................................. 12

4.4.7 Backflow prevention ................................................................................................................................... 12

5 Marking ............................................................................................................................................................ 12

6 Evaluation of conformity ........................................................................................................................... 12

6.1 General ............................................................................................................................................................. 12

6.1.1 Compliance testing ...................................................................................................................................... 12

6.1.2 Market surveillance .................................................................................................................................... 13

6.2 Initial type testing ........................................................................................................................................ 13

6.2.1 General ............................................................................................................................................................. 13

6.2.2 Actual volume ................................................................................................................................................ 13

6.2.3 Rated storage volume ................................................................................................................................. 13

6.2.4 Hot water volume ......................................................................................................................................... 13

6.2.5 Primary heating power (heat exchanger performance) ................................................................ 14

6.2.6 Durability testing ......................................................................................................................................... 14

6.2.7 Double-walled primary heaters .............................................................................................................. 14

6.2.8 Standing heat loss ........................................................................................................................................ 14

6.2.9 Pressure resistance ..................................................................................................................................... 14

6.2.10 Temperature control devices .................................................................................................................. 14

6.2.11 Heat exchanger pressure drop ................................................................................................................ 14

6.3 Production testing ....................................................................................................................................... 14

6.4 Factory production control (FPC) .......................................................................................................... 15

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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)

7 Technical documents .................................................................................................................................. 15

7.1 General ............................................................................................................................................................. 15

7.2 Assembly and maintenance instructions ............................................................................................. 15

7.3 Operating instructions ................................................................................................................................ 16

Annex A (normative) Hot water safety and performance testing ............................................................ 17

A.1 Tests required ................................................................................................................................................ 17

A.2 Test apparatus and tolerances ................................................................................................................ 17

A.3 Performance tests ........................................................................................................................................ 19

A.4 Interpretation and calculation of hot water performance results ............................................. 21

A.5 Function of safety devices.......................................................................................................................... 22

Annex B (normative) Measurement of standing heat loss for factory insulated storage

water heaters ................................................................................................................................................. 23

B.1 General ............................................................................................................................................................. 23

B.2 Apparatus ........................................................................................................................................................ 23

B.3 Test Procedure .............................................................................................................................................. 25

B.4 Calculation of Results .................................................................................................................................. 26

Annex C (informative) Inspection access .......................................................................................................... 28

Annex ZA (informative) !Relationship between this European Standard and the
requirements of Commission Delegated Regulation (EU) No 812/2013 of 18
February 2013 supplementing Directive 2010/30/EU regarding energy labelling of
water heaters, hot water storage tanks and packages of water heater and solar

device ................................................................................................................................................................ 30

Annex ZB (informative) !Relationship between this European Standard and the
requirements of Commission Regulation (EU) No 814/2013 of 2 August 2013
implementing Directive 2009/125/EC with regard to ecodesign requirements for

water heaters and hot water storage tanks ........................................................................................ 32

Bibliography ................................................................................................................................................................. 34

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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
European foreword

This document (EN 12897:2016+A1:2020) has been prepared by Technical Committee CEN/TC 164

“Water supply”, the secretariat of which is held by AFNOR.

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 August 2020, and conflicting national standards

shall be withdrawn at the latest by August 2020.

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 includes Amendment 1 approved by CEN on 2019-10-09.
This document supersedes !EN 12897:2016".

The start and finish of text introduced or altered by amendment is indicated in the text by tags !".

This document has been prepared under a mandate given to CEN by the European Commission and the

European Free Trade Association, and supports essential requirements of Commission Delegated

Regulation (EU) No 812/2013 and Commission Regulation (EU) No 814/2013.

For relationship with EU Directives, see informative Annexes ZA and ZB which are an integral part of

this document.

In comparison with EN 12897:2006, the following significant changes have been made:

— the capacity range extended from 1 000 l to 2 000 l;
— the maximum temperature reduced from 100 °C to 95 °C;

— revisions in durability testing for cylinders using expansion vessels or internal expansion space;

— provision is made in Annex A for the calculation of the V hot water capacity;

— Annex B has been revised to improve the test methodology and bring the standing heat loss test

requirements in line with those required by the EU directives for the Ecodesign and labelling of hot

water storage tanks.

!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,

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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United

Kingdom."
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
Introduction

In respect of potential adverse effects on the quality of water intended for human consumption caused

by the product covered by this standard:

a) This standard provides no information as to whether the product may be used without restriction

in any of the Member States of the EU or EFTA.

b) It should be noted that, while awaiting the adoption of the verifiable European criteria, existing

national regulations concerning the use and/or the characteristics of this product remain in force.

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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
1 Scope

This document specifies the constructional and performance requirements and methods of test for

indirectly heated, unvented (closed) storage water heaters of up to 2 000 l volume suitable for

connection to a water supply at a pressure between 0,05 MPa and 1,0 MPa (0,5 bar and 10 bar), and

fitted with control and safety devices designed to prevent the temperature of the stored drinking water

from reaching 95 °C.

Whilst storage water heaters intended primarily for direct heating are not covered by this document, it

does allow the provision of electric heating elements for auxiliary use.
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 1487, Building valves — Hydraulic safety groups — Tests and requirements
EN 1488, Building valves — Expansion groups — Tests and requirements
EN 1489, Building valves — Pressure safety valves — Tests and requirements

EN 1490, Building valves — Combined temperature and pressure relief valves — Tests and requirements

EN 1491, Building valves — Expansion valves — Tests and requirements

EN 1567, Building valves — Water pressure reducing valves and combination water pressure reducing

valves — Requirements and tests

EN 1717, Protection against pollution of potable water in water installations and general requirements of

devices to prevent pollution by backflow
EN 13203 (all parts), Gas-fired domestic appliances producing hot water

EN 13959, Anti-pollution check valves — DN 6 to DN 250 inclusive family E, type A, B, C and D

EN 15332:2007, Heating boilers — Energy assessment of hot water storage systems

EN 60379:2004, Methods for measuring the performance of electric storage water-heaters for household

purposes (IEC 60379:1987)

EN 60730-2-9, Automatic electrical controls for household and similar use — Part 2-9: Particular

requirements for temperature sensing controls (IEC 60730-2-9)
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
3 Terms, definitions and symbols

For the purposes of this document, the following terms, definitions and symbols apply.

!ISO and IEC maintain terminological databases for use in standardization at the following addresses:

• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp"
3.1 Terms and definitions
3.1.1
indirectly heated unvented (closed) storage water heater

vessel complete with heat exchanger (primary heater) for heating and storage of drinking water where

the contents are not vented to atmosphere
3.1.2
rated volume
rated storage volume
volume of the water storage vessel in litres as specified in the manual
3.1.3
actual volume
measured volume of the drinking water storage vessel in litres
3.1.4
water side
part of the storage water heater directly in contact with the drinking water
3.1.5
heating side
parts of the storage water heater which contain the heating medium
3.1.6
maximum design pressure
rated pressure

maximum pressure to which the unvented storage water heater is designed to be subjected in use

3.1.7
maximum inlet pressure
specified maximum cold water inlet pressure for the water heater
3.1.8
maximum safety temperature
maximum temperature that the stored water can reach under a fault condition
3.1.9
maximum operating temperature
maximum temperature that can be set for normal operation
3.1.10
primary heater

heat exchanger system fitted to the hot water storage vessel through which a heating medium (such as

water from a boiler) flows to heat the stored drinking water
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
3.1.11
double-walled primary heater

primary heater with concentric walls such that any leak through one wall will not allow the heating

fluid to contaminate the drinking water
3.2 Symbols
Symbol Unit Description
θ´p [ °C ] Average temperature of the water drawn off at ≥ (θc + 30) °C
V [l] Mixed water quantity delivered at 40 °C.
θc [ °C ] Average temperature of inlet cold water during the test
θ [ °C ] Target hot water temperature for hot water performance testing = θ
set c
+ 50 K
θpri [ °C ] Primary flow temperature = θc + 70 K
θ [ °C ] Target temperature of stored water for heat loss testing
e [ °C ] Mean of all the differentials between θ and measured ambient air
temperature
θa [ °C ] Measured ambient temperature at a given position
V [ l ] Volume of water drawn off at ≥ (θ + 30)°C
hot c
Qc [ kWh/24h ] Corrected 24 h heat loss
Q [ kWh/24h Declared standing heat loss
or W ]
Qm [ kWh ] Power consumption meter reading
t [ minutes ] Time taken to reheat the storage water heater from θc to θset
P [ kW ] Calculated heat exchanger performance
4 Requirements
4.1 Constructional requirements
4.1.1 Inspection access

Unvented storage water heaters shall be provided with means for internal inspection (see Annex C).

This can also be achieved by using a connection intended and dimensioned for another purpose where

the use of a suitable inspection instrument such as an endoscope is acceptable.
4.1.2 Draining

Unvented storage water heaters shall permit in situ draining. The method of draining shall be given in

the manufacturer's instructions.
4.1.3 Hydraulic connections

Hydraulic connections shall be of a type that allows the storage water heater to be disconnected from

the pipework.
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
4.2 Temperature control

The temperature of the stored drinking water shall be regulated either by control of the heat source or

sources or by control of the water heater.
4.3 Mechanical resistance and stability
4.3.1 Pressure resistance of water storage vessel

When tested in accordance with 6.2, the water heater shall withstand a pressure of 2,0 times the

maximum design pressure (as specified by the manufacturer) for a period of not less than 10 min

without showing any leakage or cracking.
4.3.2 Pressure resistance of primary heater

When tested in accordance with 6.2, the primary heater or heaters shall withstand a pressure of 2,0

times the maximum design pressure, as specified by the manufacturer, for a period of not less than

10 min without showing any leakage or cracking.
4.3.3 Durability
4.3.3.1 General

Water heaters shall be tested for durability by pressure cycle testing to either 4.3.3.2 or 4.3.3.3 as

appropriate. See Figure 2 for details. The storage water heater shall show no signs of leakage or

cracking after testing.

For water heaters without inlet pressure and system expansion control and where the internal pressure

is likely to reach maximum design pressure due to water expansion after heat input, the test in 4.3.3.2

shall be applied.

For water heaters designed for use with expansion vessels or internal expansion space such that the

rise in internal pressure due to expansion is controlled to below maximum design pressure, then the

alternative 4.3.3.3 shall be used.

If 4.3.3.3 is used then the installation manual supplied with the water heater shall specify the pressure

reduction and expansion control devices required.
4.3.3.2 Water heaters without inlet pressure and system expansion control

The water heater shall be subjected to either 20 000 periodic cycles at 1,2 × maximum design pressure

or 100 000 periodic cycles at 1,0 × maximum design pressure.

4.3.3.3 Water heaters designed for use with expansion vessels or internal expansion space

For water heaters supplied for use with inlet pressure controls and expansion control systems and

these control systems are supplied with the water heater then the water heater shall be subjected to

either 20 000 periodic cycles at 1,5 × maximum inlet pressure or 100 000 periodic cycles at

1,3 × maximum inlet pressure. This procedure is illustrated by Figure 1.
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
Key
Y pressure
X time
Figure 1 — Diagram of test pressure cycle variations
T ≥ 15 s ≤ 30 s
T ≥ 15 s ≤ 20 s
T ≥ 45 s ≤ 60 s

P = Minimum inlet pressure as defined in the technical documents or 0,1 MPa (1 bar) whichever is the

lower value.
P = Test pressure as defined in 4.3.3.2 or 4.3.3.3 as appropriate.
Key
1 optional inlet pressure control with expansion valve (4.3.3.2)
2 mandatory inlet pressure control with external expansion vessel (4.3.3.3)
3 mandatory inlet pressure control with internal expansion space (4.3.3.3)
Figure 2 — Pressure control options
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
4.3.4 Leakage test on double-walled primary heater

When a water heater is provided with a double-walled primary heater, it shall be constructed such that

any leakage from the heating side shall be routed to outside the heat exchanger without coming into

contact with the stored drinking water.
4.4 Safety equipment
4.4.1 General
Control and safety devices shall operate in the following sequence:
1) thermostatic control device;
2) energy cut out device;
3) where required, temperature pressure relief valve or safety relief valve.

Water heaters shall, where required, either be factory fitted, supplied with or fitted in accordance with

the manufacturer's instructions with all devices necessary for the operation of the water heater and the

prevention of contamination of the drinking water supply.

All tests, unless specified within the test method, shall be carried out with all devices necessary to

control the temperature of the water and all devices necessary for the operation of the water heater and

the prevention of contamination of the drinking water supply, fitted.
4.4.2 Energy cut-out device

Where required, water heaters shall be fitted with one or more non-self-resetting energy cut-outs

conforming to EN 60730-2-9 connected to the heat source to ensure that the heat input is interrupted in

the event of failure of the control thermostat and before the temperature of the stored water reaches

95 °C.
4.4.3 Temperature relief valve

Where required, a temperature relief or a temperature and pressure relief valve shall conform to

EN 1490 and be positioned in the water heater so that it prevents the temperature of the stored water

from exceeding 100 °C.
4.4.4 Pressure relief/expansion valve

Where required, water heaters shall be fitted, on the cold-water inlet, with either:

a) an expansion valve conforming to EN 1491,
b) an expansion group conforming to EN 1488,
c) a pressure safety valve conforming to EN 1489, or
d) a hydraulic safety group conforming to EN 1487.
4.4.5 Pressure reducing valve
Where required, a pressure reducing valve conforming to EN 1567 shall be used.
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
4.4.6 Provision for expansion

Where it is a local requirement that expansion water is contained within the hot water system, water

heaters shall either:
a) have an expansion capability within the storage vessel, or

b) be supplied with, or fitted in accordance with the manufacturer's instructions with an expansion

vessel.
4.4.7 Backflow prevention

Where required, a protective device against backflow conforming to EN 1717 shall be used. If non-

return valves are used, they shall comply with EN 13959.
5 Marking

Water heaters shall be permanently marked, by means of a plate or label to be visible after installation,

with, as a minimum, the following information:
a) number and year of this standard, EN 12897:2016;
b) manufacturer's name, trademark or identification mark;
c) manufacturing number or serial number, indicating year of manufacture;
d) maximum design pressure on the drinking water side;
e) maximum design pressure on the heating side;
f) rated storage volume;
g) rated volume of the heat exchanger(s);
h) standing heat loss in kWh/24h or W.

In the case of water heaters that are incorporated into heating boilers, the characteristics of the storage

water heater and the heating boiler may be shown on a common rating plate or label.

6 Evaluation of conformity
6.1 General
6.1.1 Compliance testing
The compliance of the product with the requirements o
...

SLOVENSKI STANDARD
SIST EN 12897:2016+A1:2020
01-april-2020
Oskrba z vodo - Specifikacija za posredno ogrevane neprezračevane (zaprte)
akumulacijske grelnike vode

Water supply - Specification for indirectly heated unvented (closed) storage water

heaters
Wasserversorgung - Bestimmung für mittelbar beheizte, unbelüftete (geschlossene)
Speicher-Wassererwärmer

Alimentation en eau - Prescriptions pour préparateurs d'eau chaude par accumulation à

chauffage indirect non ouverts à l'air libre (fermés)
Ta slovenski standard je istoveten z: EN 12897:2016+A1:2020
ICS:
91.140.65 Oprema za ogrevanje vode Water heating equipment
SIST EN 12897:2016+A1:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 12897:2016+A1:2020
---------------------- Page: 2 ----------------------
SIST EN 12897:2016+A1:2020
EN 12897:2016+A1
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2020
EUROPÄISCHE NORM
ICS 91.140.65
English Version
Water supply - Specification for indirectly heated
unvented (closed) storage water heaters

Alimentation en eau - Prescriptions pour préparateurs Wasserversorgung - Bestimmung für mittelbar

d'eau chaude par accumulation à chauffage indirect beheizte, unbelüftete (geschlossene) Speicher-

non ouverts à l'air libre (fermés) Wassererwärmer

This amendment A1 modifies the European Standard EN 12897:2016; it was approved by CEN on 9 October 2019.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of

this amendment into the relevant 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 amendment 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

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12897:2016+A1:2020 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 4

Introduction .................................................................................................................................................................... 5

1 Scope .................................................................................................................................................................... 6

2 Normative references .................................................................................................................................... 6

3 Terms, definitions and symbols ................................................................................................................. 7

3.1 Terms and definitions ................................................................................................................................... 7

3.2 Symbols ............................................................................................................................................................... 8

4 Requirements ................................................................................................................................................... 8

4.1 Constructional requirements ..................................................................................................................... 8

4.1.1 Inspection access ............................................................................................................................................. 8

4.1.2 Draining .............................................................................................................................................................. 8

4.1.3 Hydraulic connections ................................................................................................................................... 8

4.2 Temperature control ..................................................................................................................................... 9

4.3 Mechanical resistance and stability ......................................................................................................... 9

4.3.1 Pressure resistance of water storage vessel ......................................................................................... 9

4.3.2 Pressure resistance of primary heater.................................................................................................... 9

4.3.3 Durability ........................................................................................................................................................... 9

4.3.4 Leakage test on double-walled primary heater ................................................................................ 11

4.4 Safety equipment.......................................................................................................................................... 11

4.4.1 General ............................................................................................................................................................. 11

4.4.2 Energy cut-out device ................................................................................................................................. 11

4.4.3 Temperature relief valve .......................................................................................................................... 11

4.4.4 Pressure relief/expansion valve ............................................................................................................ 11

4.4.5 Pressure reducing valve ............................................................................................................................ 11

4.4.6 Provision for expansion ............................................................................................................................. 12

4.4.7 Backflow prevention ................................................................................................................................... 12

5 Marking ............................................................................................................................................................ 12

6 Evaluation of conformity ........................................................................................................................... 12

6.1 General ............................................................................................................................................................. 12

6.1.1 Compliance testing ...................................................................................................................................... 12

6.1.2 Market surveillance .................................................................................................................................... 13

6.2 Initial type testing ........................................................................................................................................ 13

6.2.1 General ............................................................................................................................................................. 13

6.2.2 Actual volume ................................................................................................................................................ 13

6.2.3 Rated storage volume ................................................................................................................................. 13

6.2.4 Hot water volume ......................................................................................................................................... 13

6.2.5 Primary heating power (heat exchanger performance) ................................................................ 14

6.2.6 Durability testing ......................................................................................................................................... 14

6.2.7 Double-walled primary heaters .............................................................................................................. 14

6.2.8 Standing heat loss ........................................................................................................................................ 14

6.2.9 Pressure resistance ..................................................................................................................................... 14

6.2.10 Temperature control devices .................................................................................................................. 14

6.2.11 Heat exchanger pressure drop ................................................................................................................ 14

6.3 Production testing ....................................................................................................................................... 14

6.4 Factory production control (FPC) .......................................................................................................... 15

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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)

7 Technical documents .................................................................................................................................. 15

7.1 General ............................................................................................................................................................. 15

7.2 Assembly and maintenance instructions ............................................................................................. 15

7.3 Operating instructions ................................................................................................................................ 16

Annex A (normative) Hot water safety and performance testing ............................................................ 17

A.1 Tests required ................................................................................................................................................ 17

A.2 Test apparatus and tolerances ................................................................................................................ 17

A.3 Performance tests ........................................................................................................................................ 19

A.4 Interpretation and calculation of hot water performance results ............................................. 21

A.5 Function of safety devices.......................................................................................................................... 22

Annex B (normative) Measurement of standing heat loss for factory insulated storage

water heaters ................................................................................................................................................. 23

B.1 General ............................................................................................................................................................. 23

B.2 Apparatus ........................................................................................................................................................ 23

B.3 Test Procedure .............................................................................................................................................. 25

B.4 Calculation of Results .................................................................................................................................. 26

Annex C (informative) Inspection access .......................................................................................................... 28

Annex ZA (informative) !Relationship between this European Standard and the
requirements of Commission Delegated Regulation (EU) No 812/2013 of 18
February 2013 supplementing Directive 2010/30/EU regarding energy labelling of
water heaters, hot water storage tanks and packages of water heater and solar

device ................................................................................................................................................................ 30

Annex ZB (informative) !Relationship between this European Standard and the
requirements of Commission Regulation (EU) No 814/2013 of 2 August 2013
implementing Directive 2009/125/EC with regard to ecodesign requirements for

water heaters and hot water storage tanks ........................................................................................ 32

Bibliography ................................................................................................................................................................. 34

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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
European foreword

This document (EN 12897:2016+A1:2020) has been prepared by Technical Committee CEN/TC 164

“Water supply”, the secretariat of which is held by AFNOR.

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 August 2020, and conflicting national standards

shall be withdrawn at the latest by August 2020.

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 includes Amendment 1 approved by CEN on 2019-10-09.
This document supersedes !EN 12897:2016".

The start and finish of text introduced or altered by amendment is indicated in the text by tags !".

This document has been prepared under a mandate given to CEN by the European Commission and the

European Free Trade Association, and supports essential requirements of Commission Delegated

Regulation (EU) No 812/2013 and Commission Regulation (EU) No 814/2013.

For relationship with EU Directives, see informative Annexes ZA and ZB which are an integral part of

this document.

In comparison with EN 12897:2006, the following significant changes have been made:

— the capacity range extended from 1 000 l to 2 000 l;
— the maximum temperature reduced from 100 °C to 95 °C;

— revisions in durability testing for cylinders using expansion vessels or internal expansion space;

— provision is made in Annex A for the calculation of the V hot water capacity;

— Annex B has been revised to improve the test methodology and bring the standing heat loss test

requirements in line with those required by the EU directives for the Ecodesign and labelling of hot

water storage tanks.

!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,

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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United

Kingdom."
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
Introduction

In respect of potential adverse effects on the quality of water intended for human consumption caused

by the product covered by this standard:

a) This standard provides no information as to whether the product may be used without restriction

in any of the Member States of the EU or EFTA.

b) It should be noted that, while awaiting the adoption of the verifiable European criteria, existing

national regulations concerning the use and/or the characteristics of this product remain in force.

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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
1 Scope

This document specifies the constructional and performance requirements and methods of test for

indirectly heated, unvented (closed) storage water heaters of up to 2 000 l volume suitable for

connection to a water supply at a pressure between 0,05 MPa and 1,0 MPa (0,5 bar and 10 bar), and

fitted with control and safety devices designed to prevent the temperature of the stored drinking water

from reaching 95 °C.

Whilst storage water heaters intended primarily for direct heating are not covered by this document, it

does allow the provision of electric heating elements for auxiliary use.
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 1487, Building valves — Hydraulic safety groups — Tests and requirements
EN 1488, Building valves — Expansion groups — Tests and requirements
EN 1489, Building valves — Pressure safety valves — Tests and requirements

EN 1490, Building valves — Combined temperature and pressure relief valves — Tests and requirements

EN 1491, Building valves — Expansion valves — Tests and requirements

EN 1567, Building valves — Water pressure reducing valves and combination water pressure reducing

valves — Requirements and tests

EN 1717, Protection against pollution of potable water in water installations and general requirements of

devices to prevent pollution by backflow
EN 13203 (all parts), Gas-fired domestic appliances producing hot water

EN 13959, Anti-pollution check valves — DN 6 to DN 250 inclusive family E, type A, B, C and D

EN 15332:2007, Heating boilers — Energy assessment of hot water storage systems

EN 60379:2004, Methods for measuring the performance of electric storage water-heaters for household

purposes (IEC 60379:1987)

EN 60730-2-9, Automatic electrical controls for household and similar use — Part 2-9: Particular

requirements for temperature sensing controls (IEC 60730-2-9)
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
3 Terms, definitions and symbols

For the purposes of this document, the following terms, definitions and symbols apply.

!ISO and IEC maintain terminological databases for use in standardization at the following addresses:

• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp"
3.1 Terms and definitions
3.1.1
indirectly heated unvented (closed) storage water heater

vessel complete with heat exchanger (primary heater) for heating and storage of drinking water where

the contents are not vented to atmosphere
3.1.2
rated volume
rated storage volume
volume of the water storage vessel in litres as specified in the manual
3.1.3
actual volume
measured volume of the drinking water storage vessel in litres
3.1.4
water side
part of the storage water heater directly in contact with the drinking water
3.1.5
heating side
parts of the storage water heater which contain the heating medium
3.1.6
maximum design pressure
rated pressure

maximum pressure to which the unvented storage water heater is designed to be subjected in use

3.1.7
maximum inlet pressure
specified maximum cold water inlet pressure for the water heater
3.1.8
maximum safety temperature
maximum temperature that the stored water can reach under a fault condition
3.1.9
maximum operating temperature
maximum temperature that can be set for normal operation
3.1.10
primary heater

heat exchanger system fitted to the hot water storage vessel through which a heating medium (such as

water from a boiler) flows to heat the stored drinking water
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
3.1.11
double-walled primary heater

primary heater with concentric walls such that any leak through one wall will not allow the heating

fluid to contaminate the drinking water
3.2 Symbols
Symbol Unit Description
θ´p [ °C ] Average temperature of the water drawn off at ≥ (θc + 30) °C
V [l] Mixed water quantity delivered at 40 °C.
θc [ °C ] Average temperature of inlet cold water during the test
θ [ °C ] Target hot water temperature for hot water performance testing = θ
set c
+ 50 K
θpri [ °C ] Primary flow temperature = θc + 70 K
θ [ °C ] Target temperature of stored water for heat loss testing
e [ °C ] Mean of all the differentials between θ and measured ambient air
temperature
θa [ °C ] Measured ambient temperature at a given position
V [ l ] Volume of water drawn off at ≥ (θ + 30)°C
hot c
Qc [ kWh/24h ] Corrected 24 h heat loss
Q [ kWh/24h Declared standing heat loss
or W ]
Qm [ kWh ] Power consumption meter reading
t [ minutes ] Time taken to reheat the storage water heater from θc to θset
P [ kW ] Calculated heat exchanger performance
4 Requirements
4.1 Constructional requirements
4.1.1 Inspection access

Unvented storage water heaters shall be provided with means for internal inspection (see Annex C).

This can also be achieved by using a connection intended and dimensioned for another purpose where

the use of a suitable inspection instrument such as an endoscope is acceptable.
4.1.2 Draining

Unvented storage water heaters shall permit in situ draining. The method of draining shall be given in

the manufacturer's instructions.
4.1.3 Hydraulic connections

Hydraulic connections shall be of a type that allows the storage water heater to be disconnected from

the pipework.
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
4.2 Temperature control

The temperature of the stored drinking water shall be regulated either by control of the heat source or

sources or by control of the water heater.
4.3 Mechanical resistance and stability
4.3.1 Pressure resistance of water storage vessel

When tested in accordance with 6.2, the water heater shall withstand a pressure of 2,0 times the

maximum design pressure (as specified by the manufacturer) for a period of not less than 10 min

without showing any leakage or cracking.
4.3.2 Pressure resistance of primary heater

When tested in accordance with 6.2, the primary heater or heaters shall withstand a pressure of 2,0

times the maximum design pressure, as specified by the manufacturer, for a period of not less than

10 min without showing any leakage or cracking.
4.3.3 Durability
4.3.3.1 General

Water heaters shall be tested for durability by pressure cycle testing to either 4.3.3.2 or 4.3.3.3 as

appropriate. See Figure 2 for details. The storage water heater shall show no signs of leakage or

cracking after testing.

For water heaters without inlet pressure and system expansion control and where the internal pressure

is likely to reach maximum design pressure due to water expansion after heat input, the test in 4.3.3.2

shall be applied.

For water heaters designed for use with expansion vessels or internal expansion space such that the

rise in internal pressure due to expansion is controlled to below maximum design pressure, then the

alternative 4.3.3.3 shall be used.

If 4.3.3.3 is used then the installation manual supplied with the water heater shall specify the pressure

reduction and expansion control devices required.
4.3.3.2 Water heaters without inlet pressure and system expansion control

The water heater shall be subjected to either 20 000 periodic cycles at 1,2 × maximum design pressure

or 100 000 periodic cycles at 1,0 × maximum design pressure.

4.3.3.3 Water heaters designed for use with expansion vessels or internal expansion space

For water heaters supplied for use with inlet pressure controls and expansion control systems and

these control systems are supplied with the water heater then the water heater shall be subjected to

either 20 000 periodic cycles at 1,5 × maximum inlet pressure or 100 000 periodic cycles at

1,3 × maximum inlet pressure. This procedure is illustrated by Figure 1.
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
Key
Y pressure
X time
Figure 1 — Diagram of test pressure cycle variations
T ≥ 15 s ≤ 30 s
T ≥ 15 s ≤ 20 s
T ≥ 45 s ≤ 60 s

P = Minimum inlet pressure as defined in the technical documents or 0,1 MPa (1 bar) whichever is the

lower value.
P = Test pressure as defined in 4.3.3.2 or 4.3.3.3 as appropriate.
Key
1 optional inlet pressure control with expansion valve (4.3.3.2)
2 mandatory inlet pressure control with external expansion vessel (4.3.3.3)
3 mandatory inlet pressure control with internal expansion space (4.3.3.3)
Figure 2 — Pressure control options
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
4.3.4 Leakage test on double-walled primary heater

When a water heater is provided with a double-walled primary heater, it shall be constructed such that

any leakage from the heating side shall be routed to outside the heat exchanger without coming into

contact with the stored drinking water.
4.4 Safety equipment
4.4.1 General
Control and safety devices shall operate in the following sequence:
1) thermostatic control device;
2) energy cut out device;
3) where required, temperature pressure relief valve or safety relief valve.

Water heaters shall, where required, either be factory fitted, supplied with or fitted in accordance with

the manufacturer's instructions with all devices necessary for the operation of the water heater and the

prevention of contamination of the drinking water supply.

All tests, unless specified within the test method, shall be carried out with all devices necessary to

control the temperature of the water and all devices necessary for the operation of the water heater and

the prevention of contamination of the drinking water supply, fitted.
4.4.2 Energy cut-out device

Where required, water heaters shall be fitted with one or more non-self-resetting energy cut-outs

conforming to EN 60730-2-9 connected to the heat source to ensure that the heat input is interrupted in

the event of failure of the control thermostat and before the temperature of the stored water reaches

95 °C.
4.4.3 Temperature relief valve

Where required, a temperature relief or a temperature and pressure relief valve shall conform to

EN 1490 and be positioned in the water heater so that it prevents the temperature of the stored water

from exceeding 100 °C.
4.4.4 Pressure relief/expansion valve

Where required, water heaters shall be fitted, on the cold-water inlet, with either:

a) an expansion valve conforming to EN 1491,
b) an expansion group conforming to EN 1488,
c) a pressure safety valve conforming to EN 1489, or
d) a hydraulic safety group conforming to EN 1487.
4.4.5 Pressure reducing valve
Where required, a pressure reducing valve conforming to EN 1567 shall be used.
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SIST EN 12897:2016+A1:2020
EN 12897:2016+A1:2020 (E)
4.4.6 Provision for expansion

Where it is a local requirement that expansion water is contained within the hot water system, water

heaters shall either:
a) have an expansion capability within the storage vessel, or

b) be supplied with, or fitted in accordance with the manufacturer's instructions with an expansion

vessel.
4.4.7 Backflow prevention

Where required, a protective device against backflow conforming to EN 1717 shall be used. If non-

return valves are used, they shall comply with EN 13959.
5 Marking

Water heaters shall be permanently marked, by means of a plate or label to be visible after installation,

with, as a minimum, the following information:
a) number and year of this standard, EN 12897:2016;
b) manufacturer's name, trademark or identification mark;
c) manufacturing number or serial number, indicating year of manufacture;
d) maximum design pressure on the drinking water side;
e) maximum design pressure on the heating side;
f) rated storage volume;
g) rated volume of the heat exchanger(s);
h) standing heat loss in kWh/24h or W.

In the case of water heaters that are incorporated into heating boilers, the characteristics of the storage

water heater and the heating boiler may be shown on a common rating plate or label.

6 Evaluation of conformity
6.1 General
6.1.1 Compliance testing

The compliance of the product with the requirements of this European Standard and w

...