IS 18728 : 2024 Multiple Split-System Air Conditioners and Air-to-Air Heat Pumps (VRF Air Conditioners) - Specification
| ICS 27.080; 23.120 | MED 03 |
1 SCOPE
1.1 This standard covers the requirements, method of test and the standard condition for determining the capacity and efficiency ratings of air-cooled air conditioners and air-to-air heat pumps with rated voltage up to and including 250 V, 50 Hz a.c. for single phase and up to and including 415 V, 50 Hz a.c. for three phase power supply.
NOTE - The air conditioners covered under the scope of this standard are commonly known as variable refrigerant flow (VRF) air conditioners.
1.2 This standard is applicable to the following equipments:
a) Basic multi-split systems;
b) Modular multi-split systems; and
c) Modular heat recovery multi-split systems.
These multi-split systems include air-to-air systems with non-ducted and/or ducted indoor units with integral fans and indoor units supplied without fans.
1.3 This standard is limited to the following:
a) Residential, commercial, and industrial split-system air conditioners and heat pumps;
b) Factory-made, electrically driven, and use mechanical compression;
c) Single and multiple-circuit splitsystems which utilize one or more compressors with no more than two steps of control of the outdoor unit; or
d) Split-systems with a single refrigeration circuit which utilize one or more variable-speed compressors or alternative compressor combinations for varying the capacity of the system by three or more steps.
The split-systems are designed to operate with a combination of one or more outdoor units and two or more indoor units designed for individual operation, and such modular systems are capable of transferring recovered heat from one or more indoor units to other units in the same system.
The requirements of testing and rating covered in this standard are based on the use of matched assemblies.
1.4 This standard is not applicable to the rating and testing of the following:
a) Water-cooled or water source equipment;
b) Mobile (single-duct) units having a condenser exhaust duct;
c) Individual assemblies not constituting a complete refrigeration system;
d) Equipment using the absorption refrigeration cycle;
e) Unitary and split air conditioners covered under IS 1391 (Part 1) and (Part 2);
f) Ducted and packaged air conditioners covered under IS 8148; and
g) Evaporative air cooler covered under IS 3315.
This standard does not deal with safety as the same is covered under IS/IEC 60335-2-40 for units using refrigerant of groups A1, A2, A2L and A3 as defined in IS 16656/ISO 817.
1.5 This standard also covers the determination of seasonal efficiencies or seasonal part-load performances, which provide a better indication of efficiency under actual operating conditions.
NOTE - Throughout this document, the terms 'equipment' and 'systems' mean 'multi-split air conditioners' and/or 'multi-split heat pumps'.
1.6 This standard specifies different test conditions for both cooling and heating requirements. For the purpose of testing in India, standard test conditions T1 for cooling and H1 for heating shall be followed as defined in this standard.
2 REFERENCES
The standards listed in Annex A contain provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of these standards.
| IS 302 (Part 1) : 2008 | Safety of household and similar electrical appliances: Part 1 General requirements (sixth revision) |
| IS 694 : 2010 | Polyvinyl chloride insulated unsheathed and sheathed cables/cords with rigid and flexible conductor for rated voltages up to and including 450/750 V (fourth revision) |
| IS 996 : 2009 | Single phase a.c. induction motors for general purpose (third revision) |
| IS 1391 | Room air conditioners: |
| (Part 1) : 2023 | Unitary air conditioners (fourth revision) |
| (Part 2) : 2023 | Split air conditioners (fourth revision) |
| IS 3315 : 2024 | Direct evaporative air coolers - Specification (fourth revision) |
| IS 3615 : 2020 | Glossary of terms used in refrigeration and air conditioning (second revision) |
| IS 8148 : 2018 | Ducted and package airconditioners - Specification (second revision) |
| IS 9968 (Part 1) : 1988 | Specification for elastomer insulated cables: Part 1 For working voltages upto and including 1 100 V (first revision) |
| IS 10617 : 2018 | Hermetic compressors - Specification (second revision) |
| IS 10773 : 1995 | Wrought copper tubes for refrigeration and airconditioning purposes - Specification (first revision) |
| IS 11329 : 2018 | Finned type heat exchanger for room air conditioner (first revision) |
| IS 12615 : 2018 | Line operated three phase a.c. motors (IE CODE) “Efficiency classes and performance specification” (third revision) |
| IS 16590 : 2023 | Liquid chilling package units - Specification (first revision) |
| IS 16656 : 2017/ISO 817 : 2014 | Refrigerants - Designation and safety classification |
| IS 16678 (Part 2) : 2018/ISO 5149-2 : 2014 | Refrigerating systems and heat pumps - Safety and environmental requirements: Part 2 Design, construction, testing, marking and documentation |
| IS 16753 (Part 1) : 2022/ISO 29463-1 : 2017 | High efficiency filters and filter media for removing particles from air: Part 1 Classification, performance, testing and marking (first revision) |
| IS 17570 (Part 1) : 2021/ISO 16890-1 : 2016 | Air filters for general ventilation: Part 1 Technical specifications, requirements and classification system based upon particulate matter efficiency (ePM) |
| IS/IEC 60335-2-40 : 2018 | Household and similar electrical appliances - Safety: Part 2-40 Particular requirements for electrical heat pumps, air-conditioners and dehumidifiers |
| IS/IEC 60730-2-9 : 2011 | Automatic electrical controls for household and similar use :Part 2 Particular requirements, Section 9 Temperature sensing controls |