oSIST prEN 12976-1:2012

Thermal solar systems and components - Factory made systems - Part 1: General requirements

This European Standard specifies requirements on durability, reliability and safety for Factory Made thermal solar heating systems. The standard also includes provisions for evaluation of conformity to these requirements.
The requirements in this standard apply to Factory Made solar systems as products. The installation of these systems itself is not considered, but requirements are given for the documentation for the installer and the user which is delivered with the system (see also 4.6).

Thermische Solaranlagen und ihre Bauteile - Vorgefertigte Anlagen - Teil 1: Allgemeine Anforderungen

Diese Europäische Norm legt Anforderungen hinsichtlich Dauerhaftigkeit, Zuverlässigkeit und Sicherheit für vorgefertigte Solaranlagen fest. Die Norm enthält auch Vorgaben für die Bewertung der Konformität mit diesen Anforderungen. Die Anforderungen in dieser Norm gelten für vorgefertigte Solaranlagen als Produkte. Der Einbau dieser Anlagen wird nicht berücksichtigt, es sind jedoch Anforderungen hinsichtlich der Dokumentation für den Installateur und für den Anwender, der mit diesen Anlagen beliefert wird, angegeben (siehe auch 4.6).

Installations solaires thermiques et leurs composants - Installations préfabriquées en usine - Partie 1 : Exigences générales

La présente Norme européenne spécifie les exigences de durabilité, de fiabilité et de sécurité requises des
installations solaires thermiques de chauffage préfabriquées en usine. Elle contient également des
dispositions relatives à l’évaluation de la conformité à ces exigences.
Les exigences de la présente norme s’appliquent aux installations solaires préfabriquées en usine en tant que
produits. Leur montage n’est pas pris en considération, mais des exigences relatives à la documentation
fournie avec l’installation et à destination de l’installateur et de l’utilisateur sont indiquées (voir également 4.6).

Toplotni sončni sistemi in sestavni deli - Industrijsko izdelani sistemi - 1. del: Splošne zahteve

General Information

• Status: Not Published
• Public Enquiry End Date: 30-May-2012
• ICS: 27.160 - Solar energy engineering
• Technical Committee: TOP - Thermal insulation
• Current Stage: 98 - Abandoned project (Adopted Project)
• Start Date: 07-Oct-2013
• Due Date: 12-Oct-2013
• Completion Date: 07-Oct-2013
• Ref Project: prEN 12976-1 - Thermal solar systems and components - Factory made systems - Part 1: General requirements

Relations

• Revised: SIST EN 12976-1:2006 - Thermal solar systems and components - Factory made systems - Part 1: General requirements
• Effective Date: 27-Feb-2010
• Revised: SIST EN 12976-1:2006 - Thermal solar systems and components - Factory made systems - Part 1: General requirements
• Effective Date: 18-Jan-2023
• Revised: SIST EN 12976-1:2006 - Thermal solar systems and components - Factory made systems - Part 1: General requirements
• Effective Date: 19-Jan-2023
• Revised: SIST EN 12976-1:2006 - Thermal solar systems and components - Factory made systems - Part 1: General requirements
• Effective Date: 08-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 12976-1:2012
01-april-2012
7RSORWQLVRQþQLVLVWHPLLQVHVWDYQLGHOL,QGXVWULMVNRL]GHODQLVLVWHPLGHO
6SORãQH]DKWHYH
Thermal solar systems and components - Factory made systems - Part 1: General
requirements
Thermische Solaranlagen und ihre Bauteile - Vorgefertigte Anlagen - Teil 1: Allgemeine
Anforderungen
Installations solaires thermiques et leurs composants - Installations préfabriquées en
usine - Partie 1 : Exigences générales
Ta slovenski standard je istoveten z: prEN 12976-1
ICS:
27.160 6RQþQDHQHUJLMD Solar energy engineering
oSIST prEN 12976-1:2012 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 12976-1:2012

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oSIST prEN 12976-1:2012


EUROPEAN STANDARD
DRAFT
prEN 12976-1
NORME EUROPÉENNE

EUROPÄISCHE NORM

February 2012
ICS 27.160 Will supersede EN 12976-1:2006
English Version
Thermal solar systems and components - Factory made
systems - Part 1: General requirements
Installations solaires thermiques et leurs composants - Thermische Solaranlagen und ihre Bauteile - Vorgefertigte
Installations préfabriquées en usine - Partie 1 : Exigences Anlagen - Teil 1: Allgemeine Anforderungen
générales
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 312.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12976-1:2012: E
worldwide for CEN national Members.

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oSIST prEN 12976-1:2012
prEN 12976-1:2012 (E)
Contents Page
Foreword .3
Introduction .4
1 Scope .6
2 Normative references .6
3 Terms and definitions .7
4 Requirements .7
4.1 General .7
4.1.1 Safety .7
4.1.2 Suitability for drinking water .7
4.1.3 Water contamination .7
4.1.4 Freeze resistance .8
4.1.5 Over temperature protection .8
4.1.6 Reverse flow protection .9
4.1.7 Pressure resistance .9
4.1.8 Electrical safety .9
4.2 Materials .9
4.3 Components and pipework .9
4.3.1 Collector .9
4.3.2 Supporting frame . 10
4.3.3 Piping . 10
4.3.4 Heat Exchangers . 10
4.3.5 Control system . 10
4.4 Safety equipment . 11
4.4.1 Safety valves . 11
4.4.2 Safety lines and expansion lines . 11
4.4.3 Blow-off lines . 11
4.5 Resistance to external influences . 11
4.6 Documentation . 11
4.6.1 General . 11
4.6.2 Documents for the installer . 12
4.6.3 Documents for the user . 13
4.7 Labelling . 14
4.8 System performance . 15
Annex A (informative) Conformity assessment . 16
Annex B (informative) Material combination with regard to corrosion . 17
Bibliography . 19

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oSIST prEN 12976-1:2012
prEN 12976-1:2012 (E)
Foreword
This document (prEN 12976-1:2012) has been prepared by Technical Committee CEN/TC 312 “Thermal solar
systems and components”, the secretariat of which is held by ELOT.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12976-1:2006.
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Introduction
Drinking water quality
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 verifiable European criteria, existing national
regulations concerning the use and/or the characteristics of this product remain in force.
Factory Made and Custom Built solar heating systems
The standards prEN 12976-1, prEN 12976-2, CEN/TS 12977-1, CEN/TS 12977-2, EN 12977-3, CEN/TS 12977-4
and CEN/TS 12977-5 distinguish two categories of solar heating systems: Factory Made solar heating systems
and Custom Built solar heating systems. The classification of a system as Factory Made or Custom Built is a
choice of the final supplier, in accordance with the following definitions.
Factory Made solar heating systems are batch products with one trade name, sold as complete and ready
to install kits, with fixed configurations. Systems of this category are considered as a single product and
assessed as a whole.
If a Factory Made Solar Heating System is modified by changing its configuration or by changing one or more
of its components, the modified system is considered as a new system for which a new test report is
necessary. Requirements and test methods for Factory Made solar heating systems are given in
prEN 12976-1 and prEN 12976-2.
Custom Built solar heating systems are either uniquely built, or assembled by choosing from an assortment
of components. Systems of this category are regarded as a set of components. The components are
separately tested and test results are integrated to an assessment of the whole system. Requirements for
Custom Built solar heating systems are given in CEN/TS 12977-1; test methods are specified in
CEN/TS 12977-2 and EN 12977-3. Custom Built solar heating systems are subdivided into two categories:
 Large Custom Built systems are uniquely designed for a specific situation. In general HVAC engineers,
manufacturers or other experts design them.
 Small Custom Built systems offered by a company are described in a so-called assortment file, in
which all components and possible system configurations, marketed by the company, are specified. Each
possible combination of a system configuration with components from the assortment is considered as
one Custom Built system.
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Table 1 shows the division for different system types:
Table 1 — Division for factory made and custom built solar heating systems
Factory Made Solar Heating Systems Custom Built Solar Heating Systems
(prEN 12976-1 & prEN 12976-2) (CEN/TS 12977-1, CEN/TS 12977-2 & EN 12977-3)
Integral collector-storage systems for domestic hot
Forced-circulation systems for hot water preparation
water preparation
and/or space heating, assembled using components
and configurations described in a documentation file
Thermosiphon systems for domestic hot water
(mostly small systems)
preparation
Uniquely designed and assembled systems for hot
Forced-circulation systems as batch product with
water preparation and/or space heating (mostly large
fixed configuration for domestic hot water preparation
systems)

NOTE 1 Forced circulation systems can be classified either as Factory Made or as Custom Built, depending on the
market approach chosen by the final supplier.
NOTE 2 Both Factory Made and Custom Built systems are performance tested under the same set of reference
conditions as specified in prEN 12976-2:2012, Annex B, and in CEN/TS 12977-2:2010, Annex A. In practice, the
installation conditions may differ from these reference conditions.
NOTE 3 A Factory Made system for domestic hot water preparation may have an option for space heating, however
this option should not be used or considered during testing as a Factory Made system.
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oSIST prEN 12976-1:2012
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1 Scope
This European Standard specifies requirements on durability, reliability and safety for Factory Made thermal
solar heating systems. The standard also includes provisions for evaluation of conformity to these
requirements.
The requirements in this standard apply to Factory Made solar systems as products. The installation of these
systems itself is not considered, but requirements are given for the documentation for the installer and the
user which is delivered with the system (see also 4.6).
2 Normative references
The following referenced documents are indispensable for the application of this European Standard. For
dated references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
EN 806-1, Specifications for installations inside buildings conveying water for human consumption — Part 1: General
EN 806-2, Specification for installations inside buildings conveying water for human consumption — Part 2: Design
EN 809, Pumps and pump units for liquids — General safety requirements
EN 1151 (all parts), Pumps — Rotodynamic pumps — Circulation pumps having a rated power input not
exceeding 200 W for heating installations and domestic hot water installations
EN 1489, Building valves — Pressure safety valves — Tests and requirements
EN 1490, Building valves — Combined temperature and pressure relief valves — Tests and requirements
EN 1991-1-3, Eurocode 1: Actions on structures — Part 1-3: General actions — Snow loads
EN 1991-1-4, Eurocode 1: Actions on structures — Part 1-4: General actions — Wind actions
EN 1993-1-1, Eurocode 3: Design of steel structures — Part 1-1: General rules and rules for buildings
EN 1999-1-1, Eurocode 9: Design of aluminium structures — Part 1-1: General structural rules
EN 12975-1:2006+A1:2010, Thermal solar systems and components — Solar collectors — Part 1: General
requirements
EN 12975-2, Thermal solar systems and components — Solar collectors — Part 2: Test methods
prEN 12976-2:2012, Thermal solar systems and components — Factory made systems — Part 2: Test methods
CEN/TS 12977-5, Thermal solar systems and components — Custom built systems — Part 5: Performance
test methods for control equipment
EN 15092, Building valves — Inline hot water supply tempering valves — Tests and requirements
EN 60335-1, Household and similar electrical appliances — Safety — Part 1: General requirements
(IEC 60335-1)
EN 60335-2-21, Household and similar electrical appliances — Safety — Part 2-21: Particular requirements
for storage water heaters (IEC 60335-2-21)
EN ISO 9488:1999, Solar energy — Vocabulary (ISO 9488:1999)
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3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN ISO 9488:1999 and the following apply.
3.1
expansion line
connecting line between the collectors and the pressure expansion
vessel
connecting line between the collector array and the open expansion
vessel.
3.2
safety line
connecting line between the collector array and the safety valve
connecting line between the collector array and the open expansion
vessel
3.3
blow-off line
connecting line between the outlet of the safety valve and the environment
3.4
factory-made solar system
packaged solar energy system for the purpose of hot water preparation only, either of the close-coupled or
remote-store type, consisting of either one integral component or of a uniform set and configuration of
components, produced under conditions which are presumed uniform, and offered for sale under the same
trade name
NOTE 1 A single system can be tested as a whole in a test laboratory, leading to representative results for all systems
with the same trade name, configuration, components and dimensions (see also the Introduction).
NOTE 2 External auxiliary water heating devices that are placed in series with the Factory Made system are not
considered to be part of the system. Cold water piping from the cold water grid to the system as well as piping from the
system to an external auxiliary heater or to tapping points is not considered to be part of the system. Piping between
components of the Factory Made system is considered to be part of the system. Any integrated heat exchanger or piping for
space heating option (see Introduction, Note 3) is not considered to be part of the system.
4 Requirements
4.1 General
4.1.1 Safety
The system shall fulfil general safety requirements, e.g. care shall be taken to avoid protruding sharp edges
on the outside of the system.
4.1.2 Suitability for drinking water
The system shall conform to EN 806-1 and EN 806-2.
NOTE See 4.6.2 c) 7) and 4.6.3 b) 3).
4.1.3 Water contamination
The system has to be designed to avoid water contamination for backflow from all circuits to drinking main
supplies.
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4.1.4 Freeze resistance
4.1.4.1 General
The manufacturer shall state a minimal allowed temperature for the system. The parts of the system that are
exposed to the outdoors shall be able to withstand freezing to this specified temperature without any permanent
damage.
The manufacturer shall describe the method of freeze protection used for the system.
Any indoor components that are to be installed in places where temperatures can drop below 0 °C, shall be
protected against freezing.
The freezing mechanism shall be tested in accordance with 5.1 of prEN 12976-2:2012.
4.1.4.2 Freeze protection by means of antifreeze fluid
The manufacturer shall define the composition of the heat transfer fluid, including additives, allowed for the
system.
Precautions shall be taken to prevent the antifreeze fluid from deterioration as a result of high temperature
conditions. These precautions shall be checked in accordance with 5.2 of prEN 12976-2:2012.
NOTE In general the minimal allowed temperature of the system is equal to the freezing point of the antifreeze fluid. If
the concentration of some antifreeze fluids - like glycols - exceeds a certain limit, they can freeze without damaging the
system. In this case the minimal allowed temperature can be lower than the freezing point of the antifreeze fluid.
4.1.5 Over temperature protection
4.1.5.1 General
The system shall have been designed in such a way that prolonged high solar irradiation without heat
consumption does not cause any situation in which special action by the user is required to bring the system back
to normal operation.
When the system has a provision to drain an amount of drinking water as a protection against overheating, the hot
water drain shall be constructed in such a way that no damage is done to the system or any other materials in the
house by the drained hot water. The construction shall be such that there is no danger to inhabitants from steam
or hot water from the drain (see 4.6.2).
When the overheating protection of the system is dependent on electricity supply and/or cold water supply, this
shall be stated clearly in the instructions and on the system (see 4.6.3 and 4.7).
4.1.5.2 Scald protection
When the system is tested in accordance with 5.2 of prEN 12976-2:2012, no steam shall escape from any tapping
point. When this test has been performed with other than the highest irradiations this shall be mentioned in the
documentation for the user (see 4.6.3).
For systems in which the temperature of the domestic hot water delivered to the user can exceed 60 °C, the
assembly instructions shall mention that an automatic cold water mixing device or any other device to limit the
tapping temperature to at most 60 °C +/- 5°C shall be installed on the solar heating system or elsewhere in the
domestic hot water installation (see also 4.6.2).
This device shall be able to withstand the maximum possible domestic hot water temperature from the solar
heating system.
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4.1.5.3 Over temperature protection for materials
The system shall have been designed in such a way that the maximal allowed temperature of any material in the
system is never exceeded.
NOTE Care should be taken in cases where under stagnation conditions steam or hot water can enter the collector
pipes, pipework, distribution network or heat exchanger).
4.1.6 Reverse flow protection
The system shall contain provisions in order to prevent increased heat loss resulting from reverse flow in any
circuit. This shall be checked in accordance with 5.10 of prEN 12976-2:2012.
4.1.7 Pressure resistance
The storage tank and heat exchangers in this tank shall withstand 1,5 times the manufacturer's stated
maximum individual working pressures.
When tested in accordance with 5.3 of prEN 12976-2:2012 to the above pressures, there shall be no visible
permanent damage or leakage of the system components and interconnections. After the waiting period in the
test, the hydraulic pressure shall not have dropped more than 10 % from the value measured at the start of the
waiting period.
The drinking water circuit shall withstand the maximum pressure required by national/European drinking water
regulations for open or closed drinking water installations.
The system shall have been designed in such a way that the maximal allowed pressure of any materials in the
system is never exceeded.
Every closed circuit in the system shall contain a safety valve. This safety valve shall withstand the highest
temperature that can be reached at its location. It shall conform to EN 1489. If thermostatic valves are used, these
shall conform to EN 1490.
4.1.8 Electrical safety
If the system contains any electrical devices, these shall conform to EN 60335-1 and EN 60335-2-21.
4.2 Materials
Any parts of the system to be mounted outdoors shall be resistant to UV radiation and other weather conditions
over the prescribed maintenance interval. When any maintenance or replacement of system parts is required in
order to maintain the system’s working order over a period of 10 years, this shall be clearly stated in the
documents for the user.
With respect to the materials used in the collector loop, Annex B give information to assist manufacturers in
selecting them to avoid corrosion.
4.3 Components and pipework
4.3.1 Collector
For systems whose collector can be tested separately, the collector shall conform to EN 12975-1, with the
exception of:
 internal pressure tests for absorber (see 5.3.2 of EN 12975-1:2006+A1:2010);
 freeze resistance test (see 5.3.10 of EN 12975-1:2006+A1:2010);
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 thermal performance measurement (see 5.3.9 of EN 12975-1:2006+A1:2010).
For systems whose collector cannot be tested separately (for instance integrated collector-store systems), the
whole system shall conform to EN 12975-1, with the exception of:
 internal pressure tests for absorber (see 5.3.2 of prEN 12975-1:2006+A1:2010);
 exposure test (see 5.3.4 of EN 12975-1:2006+A1:2010), on the condition that the installation manual for
the system specifies that the empty system shall be protected against prolonged exposure to solar
radiation;
 internal thermal shock test (see 5.3.6 of EN 12975-1:2006+A1:2010);
 freeze resistance test (see 5.3.10 of EN 12975-1:2006+A1:2010);
 thermal performance measurement (see 5.3.9 of EN 12975-1:2006+A1:2010).
A collector can not be tested separately (in terms of prEN 12976-1, 4.3.1) if it is not possible to perform all
function testing and performance testing according to EN 12975-2 on the collector when separated from the
storage tank.
4.3.2 Supporting frame
Manufacturer shall state the maximum possible loads for their supporting frame, in accordance with EN 1993-1-1
(Steel) and EN 1999-1-1 (Aluminum).
This shall be mentioned in the documents for the installer.
Allowance of installing the system is depending on national requirements. Guidelines can be found in
EN 1991-1-3 and EN 1991-1-4.
4.3.3 Piping
The design and materials in the system shall be such that there is no possibility of deforming, clogging or lime
deposit in its circuits that will drastically influence the system performance and safety.
With regard to corrosion, Annex B give information to assist manufacturers in selecting the materials used in
the collector loop.
Circulation pumps in the system shall conform to EN 809 and EN 1151.
4.3.4 Heat Exchangers
If the system is intended for use in areas with high water hardness and at temperatures above 60 °C, heat
exchangers in contact with drinking water shall be designed such that scaling is prevented or there shall be a
facility for cleaning.
NOTE High temperature difference between the metal surface of the heat exchanger and the surrounding drinking
water mainly causes scaling. This can be avoided by increasing the heat exchanger area.
4.3.5 Control system
When present, the collector temperature sensor shall withstand stagnation conditions as specified in
EN 12975-2 without drifting by more than 1 K.
When present, the store temperature sensor shall withstand 100 °C without reduction of the accuracy by more
than 1 K (see CEN/TS 12977-5:2010, 6.3.1.4).
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The location and installation of all temperature sensors shall ensure a good thermal contact with the part of
which the temperature shall be measured. The temperature sensors shall be insulated against ambient.
4.4 Safety equipment
4.4.1 Safety valves
Each section of the collector array, which can be shut off, shall be fitted with at least one safety valve. ICS
systems shall be fitted with at least one safety valve, which may be integrated with an inlet combination. The
safety valve shall resist the temperature conditions which it is exposed to, especially the highest temperature
that can occur. The safety valve shall resist the heat transfer medium. The safety valve shall be dimensioned
such that it can release the highest flow of hot water or steam that can occur. The dimension of the safety
valve(s) shall be proved by suitable means.
The safety valves shall conform to EN 1489.
4.4.2 Safety lines and expansion lines
If the system is equipped with a safety line, this safety line shall not be capable of being shut off.
If the system is equipped with a safety line and an expansion line, the safety line and expansion line shall be
dimensioned such, that for the highest flow of hot water or steam that can occur, at no place in the collector
loop the maximum allowed pressure is exceeded due to the pressure drop in these lines. The dimension of
the safety line and expansion line shall be proved by suitable means.
The expansion line and the safety line shall be connected and laid in such a way that any accumulations of
dirt, scale or similar impurities are avoided.
4.4.3 Blow-off lines
If the system is equipped with blow-off lines, these blow-off lines shall be laid in such a way that they cannot
freeze up and that no water can accumulate within these lines. The orifices of the blow-off lines shall be
arranged in such a way that any steam or heat transfer medium issuing from the safety valves does not cause
any risk for people, materials or environment.
The system shall be checked according to 5.6.3 of prEN 12976-2:2012.
4.5 Resistance to external influences
The components, which are exposed to the effect of weather, shall resist weathering and shall be designed,
constructed and fastened in such a way that they can withstand the weather.
In respect of lightning protection, the system should conform to IEC 61024-1.
4.6 Documentation
4.6.1 General
With each Factory Made solar heating system, the manufacturer or official supplier shall deliver documents for
assembly and installation (for the installer) and documents for operation (for the user). These documents shall be
...