IEC 63159-2-2:2021

Overview

IEC 63159-2-2:2021 is an international standard developed by the International Electrotechnical Commission (IEC) that specifies methods for measuring the performance efficiency of household electric instantaneous water heaters. This part of the IEC 63159 series focuses specifically on the efficiency of single point-of-use electric instantaneous water heaters designed for household or similar use, primarily intended for showering purposes without downstream mixing.

This standard applies to open outlet, single point-of-use electric instantaneous water heaters and defines the test conditions and procedures required for the accurate assessment of their energy efficiency. It complements and should be used in conjunction with IEC 63159-1:2021, which covers the general aspects of performance measurement for household electric instantaneous water heaters.

Key Topics

• Scope of Application
  IEC 63159-2-2 targets open outlet instantaneous water heaters used individually for a single point of use, such as showers, and excludes appliances covered by other parts of the IEC 63159 series.

• Test Conditions
  Tests must maintain strict pressure, temperature, flow, and power conditions as specified to ensure valid and repeatable energy efficiency results. All tests require operation at the appliance’s maximum power setting, with flow rates set to minimum or increased if continuous operation is not possible.

• Test Setup
  The standard provides detailed guidance on the test setup, including the installation of the appliance according to manufacturer instructions, connection of the shower hose, and the use of specific test apparatus (flow meters, thermocouples, power meters). Annex B of the standard illustrates the exact configuration for open outlet heaters.

• Load Pattern
  Energy efficiency testing uses a specific XS load pattern detailed in Annex A, simulating residential water consumption for shower use in a standardized manner.

• Efficiency Metrics

  • Static Efficiency: Measures how effectively the heater converts electrical energy to usable hot water under steady-state conditions.
  • Start-up Losses: Account for energy consumed between heater power-up and delivery of usable hot water temperature.
  • Daily Energy Demand: Quantifies the total energy consumed by the appliance during the load pattern cycle without smart operation features.

• Testing Methodology
  The standard allows accelerated test patterns by reducing the time intervals between water draw-offs if test accuracy is maintained. Energy consumption is recorded via watt-hour meters during operational periods to ensure precision.

Applications

IEC 63159-2-2:2021 is critical for manufacturers, testing laboratories, regulatory bodies, and energy efficiency program administrators involved with:

• Design and development of household electric instantaneous water heaters to ensure energy efficiency standards compliance.
• Product certification and labeling to verify efficiency claims for consumer information and regulatory adherence.
• Performance benchmarking across different models of single point-of-use water heaters.
• Energy consumption analysis for household water heating solutions aimed at reducing utility costs and environmental impact.
• Supporting energy efficiency policies and standards development initiatives worldwide.

By following this standardized test method, stakeholders can ensure appliance performance is assessed consistently and fairly, encouraging innovation in energy-saving technologies.

Related Standards

• IEC 63159-1:2021 – Household electric instantaneous water heaters – Methods for measuring the performance – Part 1: General aspects. This document provides foundational test methods and principles applicable to all parts of the IEC 63159 series.
• Additional parts of the IEC 63159 series address other types of electric instantaneous water heaters or different performance characteristics and should be consulted when applicable.
• Related ISO/IEC Directives guide the preparation and publication of IEC standards, ensuring harmonization with international standardization best practices.
• Other energy efficiency standards and regulations for water heating appliances complement IEC 63159-2-2 for comprehensive performance and sustainability assessment.

By adhering to IEC 63159-2-2:2021, manufacturers and test labs can ensure accurate, repeatable, and internationally recognized energy efficiency testing for single point-use household electric instantaneous water heaters, promoting better energy management and consumer confidence in water heating appliances.