EN ISO 9806:2025

SLOVENSKI STANDARD
01-februar-2026
Nadomešča:
SIST EN ISO 9806:2018
Sončna energija - Sprejemniki sončne energije - Preskusne metode (ISO
9806:2025)
Solar energy - Solar thermal collectors - Test methods (ISO 9806:2025)
Solarenergie - Thermische Sonnenkollektoren - Prüfverfahren (ISO 9806:2025)
Énergie solaire - Capteurs solaires thermiques - Méthodes d'essai (ISO 9806:2025)
Ta slovenski standard je istoveten z: EN ISO 9806:2025
ICS:
27.160 Sončna energija Solar energy engineering
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 9806
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2025
EUROPÄISCHE NORM
ICS 27.160 Supersedes EN ISO 9806:2017
English Version
Solar energy - Solar thermal collectors - Test methods (ISO
9806:2025)
Énergie solaire - Capteurs solaires thermiques - Solarenergie - Thermische Sonnenkollektoren -
Méthodes d'essai (ISO 9806:2025) Prüfverfahren (ISO 9806:2025)
This European Standard was approved by CEN on 2 October 2025.

This European Standard was corrected and reissued by the CEN-CENELEC Management Centre on 10 December 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 NORMALISATIO N

EUROPÄISCHES KOMITEE FÜR NORMUN G

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 ISO 9806:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 9806:2025) has been prepared by Technical Committee ISO/TC 180 "Solar
energy" in collaboration with Technical Committee CEN/TC 312 “Thermal solar systems and
components” the secretariat of which is held by NQIS/ELOT.
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 April 2026, and conflicting national standards shall be
withdrawn at the latest by April 2026.
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 ISO 9806:2017.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 9806:2025 has been approved by CEN as EN ISO 9806:2025 without any modification.

International
Standard
ISO 9806
Third edition
Solar energy — Solar thermal
2025-10
collectors — Test methods
Énergie solaire — Capteurs solaires thermiques — Méthodes
d'essai
Reference number
ISO 9806:2025(en) © ISO 2025
ISO 9806:2025(en)
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
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Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 9806:2025(en)
Contents Page
Foreword .vii
Introduction .ix
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 2
5 General . 6
5.1 Test overview — Sequence of the tests .6
5.2 Design operating range . .7
5.3 Testing of collectors with specific attributes .7
5.3.1 General .7
5.3.2 Collectors using external power sources for regular operation .7
5.3.3 Collectors with active self-protection .8
5.3.4 Collectors co-generating thermal and electrical power . .8
5.3.5 Tracking collectors .8
5.3.6 Air and liquid heating collectors .9
6 Internal pressure tests for fluid channels (liquid heating collectors only) . 9
6.1 Objective.9
6.2 Fluid channels made of non-polymeric materials .9
6.2.1 Apparatus and procedure .9
6.2.2 Test conditions .10
6.3 Fluid channels made of polymeric materials .10
6.3.1 Apparatus and procedure .10
6.3.2 Test conditions .10
6.4 Results and reporting . .10
7 Air leakage rate test (air heating collectors only) . 10
7.1 Objective.10
7.2 Apparatus and procedure .10
7.3 Test conditions .11
7.4 Results and reporting . .11
8 Standard stagnation temperature .11
8.1 Objective.11
8.2 Testing under stagnation conditions . 12
8.3 Measurement and extrapolation of the standard stagnation temperature . 12
8.4 Determining standard stagnation temperature using efficiency parameters . 13
8.5 Results and reporting . . 13
9 Exposure and half-exposure test .13
9.1 Objective. 13
9.2 Initial outdoor exposure .14
9.3 Method 1 (Outdoor exposure) .14
9.4 Method 2 (Heat transfer loop) .14
9.5 Method 3 (Indoor exposure) .14
9.6 Exposure test for collectors using active mechanism to protect against overheating . 15
9.7 Test conditions . 15
9.8 Results and reporting . . 15
10 External thermal shock test .15
10.1 Objective. 15
10.2 Apparatus and procedure . 15
10.3 Test conditions .16
10.4 Results and reporting . .16

iii
ISO 9806:2025(en)
11 Internal thermal shock test (liquid heating collectors only) .16
11.1 Objective.16
11.2 Apparatus and procedure .16
11.3 Test conditions .16
11.4 Results and reporting .16
12 Rain penetration test . 17
12.1 Objective.17
12.2 Apparatus and procedure .17
12.3 Test conditions .17
12.4 Results and reporting . .19
13 Freeze resistance test . 19
13.1 Objective.19
13.2 Freeze resistant collectors .19
13.2.1 General .19
13.2.2 Test conditions .19
13.2.3 Results and reporting . 20
13.3 Heat pipe collectors . 20
13.3.1 General . 20
13.3.2 Test conditions . 20
13.3.3 Results and reporting . 20
14 Mechanical load test with positive or negative pressure .20
14.1 Objective. 20
14.2 Apparatus and procedure .21
14.2.1 Mounting .21
14.2.2 Methods for the application of the loads .21
14.2.3 Particular specifications for tracking collectors or other specific collector types . 22
14.3 Test conditions . 22
14.4 Results and reporting . 22
15 Impact resistance test .22
15.1 Objective. 22
15.2 Test procedure . 22
15.3 Impact location . 22
15.4 Method 1: Impact resistance test using ice balls . 23
15.4.1 Apparatus . 23
15.4.2 Ice balls . 23
15.4.3 Specific aspects of the test procedure using ice balls . 23
15.5 Method 2: Impact resistance test using steel balls . 23
15.6 Results and reporting . .24
16 Active self-protection mechanisms.24
16.1 Objective.24
16.2 Apparatus and procedure .24
16.3 Test conditions .24
16.3.1 Loss of power test .24
16.3.2 Loss of communication test .24
16.3.3 Overheating protection test . 25
16.3.4 Adverse climatic conditions protection test . 25
16.4 Results and reporting . 25
17 Final inspection .25
17.1 Objective. 25
17.2 Test procedure . 25
17.3 Results and reporting . 26
18 Thermal performance testing .26
18.1 General . 26
19 Collector mounting and location .27
19.1 General .27

iv
ISO 9806:2025(en)
19.2 Shading from direct solar irradiance .27
19.3 Diffuse and reflected solar irradiance .27
19.4 Thermal irradiance.27
20 Instrumentation .28
20.1 Solar radiation measurement . 28
20.1.1 Pyranometer . 28
20.2 Thermal radiation measurement . 28
20.3 Temperature measurements . . 28
20.3.1 Heat transfer fluid temperatures (liquid heating collectors) . 28
20.3.2 Volume flow weighted mean temperature ϑ (air heating collectors). 29
m,th
20.3.3 Measurement of ambient air temperature . 29
20.4 Flow rate measurement. 30
20.4.1 Measurement of mass flow rate (liquid) . 30
20.4.2 Measurement of collector fluid flow rate (air heating collectors) . 30
20.5 Measurement of air speed over the collector . 30
20.5.1 General . 30
20.5.2 Required accuracy .31
20.5.3 Mounting of sensors for the measurement of air velocity over the collector.31
20.6 Elapsed time measurement .31
20.7 Humidity ratio (air collectors) .31
20.8 Collector dimensions.31
21 Test installation .31
21.1 Liquid heating collectors .31
21.1.1 General .31
21.1.2 Heat transfer fluid .32
21.1.3 Pipe work and fittings .32
21.2 Air heating collectors . 33
21.2.1 General . 33
21.2.2 Closed loop test circuit. 33
21.2.3 Open to ambient test circuit . 34
21.2.4 Heat transfer fluid . 34
21.2.5 Pump and flow control devices . 34
21.2.6 Air ducts . 34
21.2.7 Fan and flow control devices . 35
21.2.8 Air preconditioning apparatus . 35
21.2.9 Humidity ratio . 35
22 Thermal performance test procedures .35
22.1 General . 35
22.2 Preconditioning of the collector . 36
22.3 Test conditions . 36
22.3.1 General . 36
22.3.2 Flow rates . 36
22.3.3 Air speed parallel to the collector plane . 36
22.4 Test procedure .37
22.4.1 General .37
22.4.2 Steady-state method .37
22.4.3 Quasi-dynamic testing .37
22.5 Measurements . . 38
22.5.1 General . 38
22.5.2 Data acquisition requirements . 38
22.6 Test period . 38
22.6.1 Steady-state testing . 38
22.6.2 Quasi-dynamic testing . 39
22.7 Performance test using a solar irradiance simulator .42
22.7.1 General .42
22.7.2 Solar irradiance simulator for thermal performance testing .42
22.7.3 Additional measurements during tests in solar irradiance simulators .43

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ISO 9806:2025(en)
22.7.4 Solar irradiance simulator for the measurement of incidence angle modifiers . 44
23 Computation of the collector parameters .44
23.1 Liquid heating collectors . 44
23.1.1 General . 44
23.1.2 Steady-state test method for liquid heating collectors . 44
23.1.3 Quasi-dynamic test method for liquid heating collectors .45
23.1.4 Data analysis .45
23.2 Air heating collectors .45
23.2.1 General .45
23.2.2 Steady-state test method for closed loop air heating collectors .45
23.2.3 Steady-state test method for open to ambient air heating collectors . 46
23.3 Standard reporting conditions (SRC) . 46
23.4 Standard uncertainties .47
23.5 Reference area conversion .47
24 Determination of the effective thermal capacity and the time constant . 47
24.1 General .47
24.2 Measurement of the effective thermal capacity with irradiance .47
24.3 Measurement of the effective thermal capacity using the quasi-dynamic method . 48
24.4 Calculation method for the determination of the effective thermal capacity . 48
24.5 Determination of collector time constant . 48
25 Determination of the incidence angle modifier (IAM) .49
25.1 General . 49
25.2 Modelling . 50
25.2.1 General . 50
25.2.2 Steady-state method .51
25.2.3 Quasi-dynamic method .51
25.3 Test procedures .52
25.3.1 Steady-state liquid heating collectors .52
25.4 Calculation of the collector incidence angle modifier.52
25.5 Reporting . 53
26 Determination of the pressure drop .53
26.1 General . 53
26.2 Liquid heating collectors . 53
26.2.1 Apparatus and procedure . 53
26.2.2 Pressure drop caused by fittings . 53
26.2.3 Test conditions . 54
26.3 Air heating collectors . 54
26.3.1 Apparatus and procedure .
...