IEC 63159-2-1:2021

Household electric instantaneous water heaters - Methods for measuring the performance - Part 2-1: Multifunctional electric instantaneous water heaters

IEC 63159-2-1:2021 applies to electric instantaneous water heaters designed to operate as multifunctional appliances with an electric rated power > 2 kW.
This document specifies tests for the assessment of the performance.
This International Standard is to be used in conjunction with IEC 63159-1:2021.

Chauffe-eau instantanés électrodomestiques - Méthodes de mesure de l’aptitude à la fonction - Partie 2-1: Chauffe-eau instantanés électriques multifonctions

L'IEC 63159-2-1:2021 s'applique aux chauffe-eau instantanés électriques conçus pour fonctionner comme des appareils multifonctions de puissance électrique assignée > 2 kW.
Le présent document spécifie les essais pour l'évaluation de l'aptitude à la fonction.
La présente Norme internationale doit être utilisée conjointement avec l'IEC 63159-1:2021.

General Information

• Status: Published
• Publication Date: 20-Oct-2021
• ICS: 91.140.65 - Water heating equipment
• Technical Committee: SC 59C - Electrical heating appliances for household and similar purposes
• Current Stage: PPUB - Publication issued
• Completion Date: 21-Oct-2021

Standards Content (Sample)

IEC 63159-2-1
Edition 1.0 2021-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Household electric instantaneous water heaters – Methods for measuring the
performance –
Part 2-1: Multifunctional electric instantaneous water heaters
Chauffe-eau instantanés électrodomestiques – Méthodes de mesure de
l'aptitude à la fonction –
Partie 2-1: Chauffe-eau instantanés électriques multifonctions
IEC 63159-2-1:2021-10(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 63159-2-1
Edition 1.0 2021-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Household electric instantaneous water heaters – Methods for measuring the
performance –
Part 2-1: Multifunctional electric instantaneous water heaters
Chauffe-eau instantanés électrodomestiques – Méthodes de mesure de
l'aptitude à la fonction –
Partie 2-1: Chauffe-eau instantanés électriques multifonctions
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 91.140.65 ISBN 978-2-8322-1040-6

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 63159-2-1:2021 © IEC 2021
CONTENTS

FOREWORD ........................................................................................................................... 4

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

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

3 Terms and definitions ...................................................................................................... 6

4 General test conditions .................................................................................................... 8

4.3 General conditions ..................................................................................................... 8

4.4 Test setup .................................................................................................................. 8

4.101 Symbols and units .................................................................................................. 8

4.102 Time constants (measuring time) ............................................................................ 9

4.103 Test setup .............................................................................................................. 9

4.103.1 Measurement setup ............................................................................................. 9

4.103.2 Setpoints ............................................................................................................. 9

4.103.3 Measurement of flow pressure and flow rate ........................................................ 9

4.103.4 Temperature measurement .................................................................................. 9

5 Energy efficiency ........................................................................................................... 10

6 Performance tests ......................................................................................................... 10

6.1 Determination of classification factor CF ............................................................... 10

6.1.1 General ......................................................................................................... 10

6.1.2 Definition of a reference instantaneous water heater ..................................... 10

6.1.3 Calculation method of nominal energy consumption ....................................... 11

6.1.4 Determination of energy demand of the sample ............................................. 11

6.1.5 Definition of classes H and E ......................................................................... 11

6.2 Determination of flow rates ................................................................................... 11

6.2.1 General ......................................................................................................... 11

6.2.2 E class water heater ...................................................................................... 11

6.2.3 H class water heater ...................................................................................... 12

6.2.4 Determination of the flow rate as a function of the pressure difference .......... 13

6.3 Pressure difference on activation of the heating capacity ...................................... 13

6.3.1 General ......................................................................................................... 13

6.3.2 E class water heater ...................................................................................... 13

6.3.3 H class water heater ...................................................................................... 13

6.4 Behaviour at switch-on of the appliance ................................................................ 14

6.4.1 General ......................................................................................................... 14

6.4.2 E class water heater ...................................................................................... 14

6.4.3 H class water heater ...................................................................................... 15

6.5 Behaviour following the change of the flow rate .................................................... 15

6.5.1 General ......................................................................................................... 15

6.5.2 E class water heater ...................................................................................... 15

6.5.3 H class water heater ...................................................................................... 16

6.6 Behaviour following interruption of the flow ........................................................... 17

6.6.1 General ......................................................................................................... 17

6.6.2 E class water heater ...................................................................................... 17

6.6.3 H class water heater ...................................................................................... 18

6.7 Behaviour at constant temperature setting ............................................................ 19

6.7.1 General ......................................................................................................... 19

6.7.2 E class water heater ...................................................................................... 19

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IEC 63159-2-1:2021 © IEC 2021 – 3 –

6.7.3 H class water heater ...................................................................................... 19

6.8 Behaviour following the change of the temperature selector setting ...................... 19

6.8.1 General ......................................................................................................... 19

6.8.2 Electronically controlled appliances ............................................................... 19

6.8.3 H class water heater ...................................................................................... 20

6.9 Behaviour at voltage limits .................................................................................... 20

6.10 Additional tests for electronic instantaneous water heaters ................................... 21

6.10.1 General ......................................................................................................... 21

6.10.2 Behaviour of the outlet temperature at decreasing water inlet

temperature ................................................................................................... 21

6.10.3 Behaviour of the outlet temperature at changing water inlet temperature ....... 22

Annex A (normative) Load pattern ........................................................................................ 23

Annex B (normative) Test setup ........................................................................................... 24

Bibliography .......................................................................................................................... 29

Figure B.101 – Single point (vented) ..................................................................................... 24

Figure B.102 – Multi point (unvented) ................................................................................... 25

Figure B.103 – Test setup ..................................................................................................... 26

Figure B.104 – Damping device (Detail 4) ............................................................................. 27

Figure B.105 – Water connection part (Detail 5) .................................................................... 27

Figure B.106 – Water connection part (Detail 6) .................................................................... 28

Table 101 – Symbols and units ............................................................................................... 8

Table 102 – Nominal values for E class water heater ............................................................ 12

Table 103 – Nominal values for H class water heater ............................................................ 12

Table 104 – Flow pressure and flow rate for multi point appliances ....................................... 13

Table 105 – Flow pressure and flow rate for single point appliances ..................................... 13

Table 106 – Pressure difference and flow rate ...................................................................... 13

Table 107 – Pressure difference and flow rate ...................................................................... 14

Table 108 – Behaviour at switch on of the appliance at different temperature selector

settings ................................................................................................................................. 15

Table 109 – Behaviour at switch on of the appliance at different settings .............................. 15

Table 110 – Behaviour following the change of the flow rate at different temperature

selector settings ................................................................................................................... 16

Table 111 – Behaviour following the change of the flow rate at different settings .................. 17

Table 112 – Behaviour following interruption of the flow ........................................................ 18

Table 113 – Behaviour following interruption of the flow ........................................................ 18

Table 114 – Behaviour at constant temperature setting ......................................................... 19

Table 115 – Behaviour following the change of the temperature selector setting at a

flow rate of 50% .................................................................................................................... 20

Table 116 – Behaviour following the change of the temperature selector setting at a

flow rate of 100% .................................................................................................................. 20

Table 117 – Behaviour at voltage limits ................................................................................. 21

Table 118 – Behaviour of the outlet temperature at decreasing water inlet temperature ....... 22

Table 119 – Behaviour of the outlet temperature following the increase of the water

inlet temperature ................................................................................................................... 22

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– 4 – IEC 63159-2-1:2021 © IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD ELECTRIC INSTANTANEOUS WATER HEATERS –
METHODS FOR MEASURING THE PERFORMANCE –
Part 2-1: Multifunctional electric instantaneous water heaters
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

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rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 63159-2-1 has been prepared by subcommittee 59C: Electrical

heating appliances for household and similar purposes, of IEC technical committee 59:

Performance of household and similar electrical appliances.
The text of this International Standard is based on the following documents:
Draft Report on voting
59C/268/FDIS 59C/272/RVD

Full information on the voting for its approval can be found in the report on voting indicated in

the above table.
The language used for the development of this International Standard is English.
---------------------- Page: 6 ----------------------
IEC 63159-2-1:2021 © IEC 2021 – 5 –

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available

at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are

described in greater detail at www.iec.ch/standardsdev/publications.
This International Standard is to be used in conjunction with IEC 63159-1:2021.

This standard supplements or modifies the corresponding clauses in IEC 63159-1. When a

particular subclause of IEC 63159-1 is not mentioned in this standard, that subclause is

applicable as far as reasonable. Where this standard states "addition", "modification" or

"replacement", the relevant requirements, test specifications or explanatory matter in

IEC 63159-1 should be adapted accordingly.

Subclauses or figures that are additional to those in IEC 63159-1 are numbered starting from

101. Additional annexes are lettered AA, BB, etc.

A list of all the parts in the IEC 63159 series, published under the general title Household

electric instantaneous water heaters – Methods for measuring the performance, can be found

on the IEC website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under webstore.iec.ch in the data related to the

specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
---------------------- Page: 7 ----------------------
– 6 – IEC 63159-2-1:2021 © IEC 2021
HOUSEHOLD ELECTRIC INSTANTANEOUS WATER HEATERS –
METHODS FOR MEASURING THE PERFORMANCE –
Part 2-1: Multifunctional electric instantaneous water heaters
1 Scope
This clause of IEC 63159-1:2021 is applicable with the following exception:
Addition:

This document applies to electrical instantaneous water heaters designed to operate as

multifunctional appliances with an electric rated power > 2 kW.
This document specifies tests for the assessment of the performance.
2 Normative references
This clause of IEC 63159-1:2021 is applicable with the following exception:
Addition:

IEC 63159-1:2021, Household electric instantaneous water heaters – Methods for measuring

the performance – Part 1: General aspects
3 Terms and definitions
This clause of IEC 63159-1 is applicable with the following exceptions:
Addition:
3.101
setpoint value

changeable value that is allocated to the appliance or the individual components thereof

3.102
pressure drop on activation of the heating capacity

pressure drop in the instantaneous water heater, at which the heating capacity is, and remains,

activated
3.103
90 % method
stop point of the measurement when 90% of value is reached

Note 1 to entry: Usually, a physical value reaches a final (average) value in an asymptotic manner. To reach a valid

measurement result, a stop point of the measurement has to be defined. The measurement is stopped when the

value finally reaches 90 % of the difference between the (average) starting value and the (average) final value.

3.104
10 %/90 % method
range between the start and stop points
---------------------- Page: 8 ----------------------
IEC 63159-2-1:2021 © IEC 2021 – 7 –

Note 1 to entry: Usually, a physical value changes with a time delay in an asymptotic manner between the start

value and the final value. To reach a valid measurement result, a start point and a stop point have to be defined for

the measurement. The measurement is started when the physical value first reaches 10 % of the difference between

the (average) starting value and the (average) final value. The measurement is stopped when the value finally

reaches 90 % of the difference.
3.105
response time

time interval between the beginning of the changing of a value or parameter and the moment a

steady-state condition is obtained
Note 1 to entry: The 90 % method shall be used.
3.106
flow rate
rate at which water flows, expressed in l/min
3.107
heating-up duration

time interval between the opening of the withdrawal device and the obtainment of the final outlet

temperature
Note 1 to entry: The 90 % method shall be used.
3.108
pressure difference

difference between the pressure at the water inlet and the water outlet of the appliance at a

defined flow rate
---------------------- Page: 9 ----------------------
– 8 – IEC 63159-2-1:2021 © IEC 2021
3.109
multifunctional appliances

instantaneous water heater that shall supply one or more outlets suitable for several functions,

for instance kitchen sinks, hand-washing sinks, showers and bathtubs
4 General test conditions
This clause of IEC 63159-1:2021 is applicable with the following exceptions:
4.3 General conditions
Modification:
The cold water temperature T shall be 15 °C ± 5 °C for the performance tests.
cold
4.4 Test setup
This subclause of IEC 63159-1:2021 is not applicable.
Addition:
4.101 Symbols and units
For the purposes of this document, the symbols and units of Table 101 apply.
Table 101 – Symbols and units
Symbol Unit Description

T °C The minimum setting of the temperature setting mechanism settable by user at which

min
the appliance heats.

If no user-accessible temperature selector is available, the relevant measurements

with T are not performed.
min

T °C Standard hot water temperature setpoint for various tests: 38 °C. If the temperature

setting mechanism settable by user does not permit an outlet temperature setting of

38 °C, a temperature as close as possible above 38 °C as possible shall be chosen.

This temperature shall be stated in the test report and shall be used for any further

measurements, instead of 38 °C.

The positions of the temperature setting mechanism shall be marked for reproducible

settings, taking into consideration the fact that T settings may depend on the
direction of the rotation of a knob.
If no user-accessible temperature selector is available, the temperature factory
setting is defined to be the T setting.

T °C The maximum setting of the temperature setting mechanism settable by the user.

max

If no user accessible temperature selector is available, the relevant measurements

with T are not performed.
max

T °C Temperature at the minimum permanent setting of the power selector settable by user

Pmin
at which the appliance heats.

If no user-accessible power selector is available, the relevant measurements with

T are not performed.
Pmin

°C Temperature at the maximum permanent setting of the power selector settable by

Pmax
user.

If no user-accessible power selector is available, the temperature factory setting is

defined to be the T setting.
Pmax

l/min The flow rate where the power consumption is 90 % of rated power at T and an inlet

V 38
90 % P
temperature of 15 °C.
Factor 

K The correction value for V if the inlet temperature differs by more than 1 K from

V 90 % P
15 °C.
---------------------- Page: 10 ----------------------
IEC 63159-2-1:2021 © IEC 2021 – 9 –
Symbol Unit Description
l/min The flow rate related to the outlet temperature of 38 °C.
T °C Temperature from which counting of useful energy content starts.
°C Minimum (peak) temperature to be achieved during tapping.
T °C Cold water inlet temperature.
cold
F l/min Minimum flow rate to be reached during tapping.
P kW Minimum required instantaneous heating power to fulfil tapping.
min
T S Tapping duration.
P kW Minimum requited heating power of the appliance.
real
kW Nominal heating power of the appliance.
nom
Q kWh Nominal daily energy consumption of the appliance.
nom
Q kWh Real daily energy consumption of the appliance.
4.102 Time constants (measuring time)
Time constants shall be determined by means of the 10 %/90 % method.
4.103 Test setup
4.103.1 Measurement setup
The appliance shall be fixed in accordance with the installation instructions.

The measurement setup shall correspond to Figure B.101 for open-outlet appliances (single

point) and to Figure B.102 for closed-outlet (multi point) appliances.
4.103.2 Setpoints

Unless no specific setpoints for the individual test are defined, all non-user adjustable set-points

shall be adjusted in accordance with the manufacturer's instructions for a standard setup.

User adjustable selectors have to be set as follows:

– If the appliance has a power selector, the selector shall be adjusted to the highest value.

– If the appliance has a temperature-independent flow selector, it shall be adjusted to the

highest value.

– If the appliance has a flow-independent temperature selector, it shall be adjusted to the

highest value.
– All other selectors shall be set in accordance with the manufacture
...