SIST-TP CEN/TR 17608:2022
(Main)State of the art on the use of flammable refrigerant alternatives, in particular from class A3, in refrigeration, air conditioning and heat pump equipment
State of the art on the use of flammable refrigerant alternatives, in particular from class A3, in refrigeration, air conditioning and heat pump equipment
This document provides the results of a comprehensive assessment of the state of the art on the use of flammable refrigerants, in particular from class A3.
Refrigerants from class B (toxic) are excluded from this scope.
This document includes the following elements:
• A segmentation of the refrigeration, air conditioning and heat pump market, making use of existing studies and research, including an assessment of safety-related barriers to the uptake of flammable refrigerants in particular from class A3 across all relevant applications;
• An assessment of the way risk assessments is used in existing standards for refrigeration, air conditioning and heat pump equipment and in other standards and a review of available risk assessment research to be taken into account including identification of potential needs for additional research;
• Analysis of:
• the relationship between risk and increased charge;
• the acceptability of increased risk compared to the risk presented by other technologies;
• the options for additional mitigation methods if the risk increase is unacceptable;
• Review of existing standards and work programmes and identification of standards that should be further updated under existing or future standardisation requests based on relevant product safety legislation, in particular with regard to allowable charge sizes of flammable refrigerants, taking into account available technology as well as emerging research and development;
• Identification of options for performance based requirements that result from risk assessments to enable the use of all flammable substances;
• Identification of options for risk minimisation and for offering flexibility in application of mitigation measures.
eptable.
Stand der Technik über die Verwendung von brennbaren Kältemitteln, insbesondere der Klasse A3, als Alternativen in Kälte-, Klima- und Wärmepumpenanlagen
Dieses Dokument liefert die Ergebnisse einer umfassenden Bewertung des Standes der Technik zum Einsatz brennbarer Kältemittel, insbesondere der Klasse A3.
Kältemittel der Toxizitätsklasse B sind von diesem Anwendungsbereich ausgenommen.
Dieses Dokument enthält die folgenden Elemente:
Eine Segmentierung des Marktes für Kälte-, Klima- und Wärmepumpen unter Nutzung vorhandener Studien und Forschungsergebnisse, einschließlich einer Bewertung sicherheitsrelevanter Hindernisse für die Aufnahme brennbarer Kältemittel, insbesondere der Klasse A3, über alle relevanten Anwendungen hinweg;
Eine Bewertung der Art und Weise, wie Risikobeurteilungen in bestehenden Normen für Kälte-, Klima- und Wärmepumpenanlagen und in anderen Normen verwendet werden, und eine Überprüfung der verfügbaren Forschungsergebnisse zur Risikobeurteilung, die berücksichtigt werden sollen, einschließlich der Ermittlung potenzieller Notwendigkeiten für zusätzliche Forschung;
Analyse der:
Beziehung zwischen Risiko und erhöhter Füllmenge;
Akzeptanz eines erhöhten Risikos im Vergleich zum Risiko anderer Technologien;
Optionen für zusätzliche Methoden zur Risikominderung, wenn die Zunahme des Risikos nicht akzeptabel ist;
Überprüfung bestehender Normen und Arbeitsprogramme und Ermittlung von Normen, die im Rahmen bestehender oder zukünftiger Normungsaufträge auf der Grundlage relevanter Produktsicherheitsgesetze weiter aktualisiert werden sollten, insbesondere im Hinblick auf zulässige Füllmengen brennbarer Kältemittel, unter Berücksichtigung verfügbarer und neuer Technologien sowie Forschung und Entwicklung;
Identifizierung von Optionen für leistungsbasierte Anforderungen, die sich aus Risikobeurteilungen ergeben, um die Verwendung aller brennbaren Stoffe zu ermöglichen;
Identifizierung von Optionen zur Risikominimierung und zur Ermöglichung von Flexibilität bei der Anwendung von Maßnahmen zur Risikominderung.
État de l'art sur l'utilisation de fluides frigorigènes inflammables de substitution, en particulier de la classe A3, dans les équipements de réfrigération, de climatisation et de pompes à chaleur
Le présent document fournit les résultats d'une évaluation complète de l'état de l'art sur l'utilisation des fluides frigorigènes inflammables, en particulier de la classe A3.
Les fluides frigorigènes de la classe B (toxiques) sont exclus du présent domaine d'application.
Le présent document comprend les éléments suivants :
• une segmentation du marché de la réfrigération, de la climatisation et des pompes à chaleur, en s'appuyant sur les études et recherches existantes, y compris une évaluation des obstacles liés à la sécurité pour l'adoption des fluides frigorigènes inflammables, en particulier ceux de la classe A3, dans toutes les applications pertinentes ;
• une évaluation de la manière dont les appréciations du risque sont utilisées dans les normes existantes pour les équipements de réfrigération, de climatisation et de pompes à chaleur et dans d'autres normes, ainsi qu'un examen des recherches disponibles à prendre en compte en matière d'appréciation du risque, y compris l'identification de l'éventuelle nécessité de recherches supplémentaires ;
• l'analyse de :
• la relation entre le risque et l'augmentation de la charge ;
• l'acceptabilité du risque accru par rapport au risque présenté par d'autres technologies ;
• les options relatives aux méthodes d'atténuation supplémentaires si l'augmentation du risque est inacceptable ;
• un examen des normes et des programmes de travail existants et l'identification des normes qu'il convient de mettre à jour dans le cadre des demandes de normalisation existantes ou futures, sur la base de la législation pertinente en matière de sécurité des produits, en particulier en ce qui concerne les capacités de charge admissibles des fluides frigorigènes inflammables, en tenant compte des technologies disponibles ainsi que des activités de recherche et développement émergentes ;
• l'identification d'options pour les exigences fondées sur les performances qui résultent des appréciations du risque afin de permettre l'utilisation de toutes les substances inflammables ;
• l'identification d'options permettant de réduire les risques au minimum et d'offrir une certaine flexibilité dans l'application des mesures d'atténuation.
Stanje tehnike na področju uporabe vnetljivih nadomestnih hladilnih sredstev, zlasti iz razreda A3, v opremi za hlajenje, klimatizacijo in toplotnih črpalkah
Ta dokument podaje rezultate celovite ocene stanja tehnike na področju uporabe vnetljivih hladilnih sredstev, zlasti tistih iz razreda A3.
Hladilna sredstva iz razreda B (strupena) so izključena iz področja uporabe tega dokumenta.
To tehnično poročilo vključuje naslednje postavke:
• segmentacijo trga hladilne opreme, klimatskih naprav in toplotnih črpalk z uporabo obstoječih
študij in raziskav, vključno z oceno varnostnih ovir za vnos vnetljivih
hladilnih sredstev, zlasti tistih iz razreda A3, v vse ustrezne vrste uporabe;
• oceno načina uporabe ocen tveganja v obstoječih standardih za hladilno opremo,
klimatske naprave in toplotne črpalke ter v drugih standardih oziroma pregled razpoložljivih raziskav z oceno tveganja, ki jih je treba upoštevati, vključno z opredelitvijo morebitnih potreb po dodatnih
raziskavah;
• analizo:
– razmerja med tveganjem in povečano obremenitvijo;
– sprejemljivosti povečanega tveganja v primerjavi s tveganjem, ki ga predstavljajo druge tehnologije;
– možnosti za dodatne metode ublažitve, če je povečanje tveganja nesprejemljivo.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
01-junij-2022
Stanje tehnike na področju uporabe vnetljivih nadomestnih hladilnih sredstev,
zlasti iz razreda A3, v opremi za hlajenje, klimatizacijo in toplotnih črpalkah
State of the art on the use of flammable refrigerant alternatives, in particular from class
A3, in refrigeration, air conditioning and heat pump equipment
Stand der Technik über die Verwendung von brennbaren Kältemitteln, insbesondere der
Klasse A3, als Alternativen in Kälte-, Klima- und Wärmepumpenanlagen
État de l'art sur l'utilisation de fluides frigorigènes inflammables de substitution, en
particulier de la classe A3, dans les équipements de réfrigération, de climatisation et de
pompes à chaleur
Ta slovenski standard je istoveten z: CEN/TR 17608:2022
ICS:
71.100.45 Hladiva in antifrizi Refrigerants and antifreezes
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
CEN/TR 17608
TECHNICAL REPORT
RAPPORT TECHNIQUE
April 2022
TECHNISCHER BERICHT
ICS 71.100.45
English Version
State of the art on the use of flammable refrigerant
alternatives, in particular from class A3, in refrigeration,
air conditioning and heat pump equipment
État de l'art sur l'utilisation de fluides frigorigènes Stand der Technik über die Verwendung von
inflammables de substitution, en particulier de la brennbaren Kältemitteln, insbesondere der Klasse A3,
classe A3, dans les équipements de réfrigération, de als Alternativen in Kälte-, Klima- und
climatisation et de pompes à chaleur Wärmepumpenanlagen
This Technical Report was approved by CEN on 20 March 2022. It has been drawn up by the Technical Committee CEN/TC 182.
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, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 17608:2022 E
worldwide for CEN national Members.
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Segmentation of the Industry Sector . 7
4.1 General. 7
4.2 Commercial applications . 7
4.2.1 Commercial Refrigeration . 7
4.2.2 Professional Refrigerated Products . 7
4.2.3 Commercial versus professional cabinets . 8
4.3 Industrial applications . 8
4.4 Chillers and heat pumps with water heat sink, indirect systems . 9
4.5 Air to air air conditioning and heat pumps . 9
4.6 Transport applications . 10
5 Current practice in the sector . 10
6 Design measures for flammable refrigerants . 12
6.1 General. 12
6.2 Design measures . 13
7 Assessment of the way risk analysis is used . 17
7.1 General. 17
7.2 Risk assessment techniques . 17
7.3 Risk acceptance criteria . 18
7.4 Assessment of the use of risk-analysis in existing standards . 19
7.5 Review of available risk assessment and potential additional research needs . 20
7.6 Analysis of relationship between risk and increased charge . 20
7.7 Acceptability of increased risk. 21
7.7.1 General. 21
7.7.2 Method of assessing risk in other applications . 22
7.8 Additional mitigation requirements . 23
7.8.1 General. 23
7.8.2 Options for additional mitigation requirements . 23
8 Relevant Legislation and Standards . 24
8.1 Relevant legislation. 24
8.2 European legislative framework . 25
8.3 Relevant standards . 25
8.3.1 General. 25
8.3.2 Risk assessment standards . 26
8.3.3 Safety standards . 27
8.3.4 Other standards . 27
8.4 Review of work programmes . 30
8.5 Identify standards that should be further developed or updated . 30
8.5.1 General. 30
8.5.2 High priority . 31
8.5.3 Medium priority . 31
8.5.4 Low priority . 32
9 Assessment of safety-related barriers . 32
9.1 European Directives . 32
9.2 Competence of service personnel – EN13313 . 32
9.3 National and regional regulations . 33
9.4 EN 378 . 33
9.5 IEC 60335-2-40 . 34
9.6 IEC 60335-2-89 . 34
9.7 Transport refrigeration . 34
10 Options . 34
10.1 Options for additional mitigation requirements . 34
10.2 Options for performance based requirements . 38
10.3 Options for risk minimisation . 38
10.4 Options for installation, operation, service, and decommissioning . 38
10.4.1 Charge size limits . 38
10.4.2 Associated risk mitigation requirements . 38
10.4.3 Design of rooms . 39
10.4.4 Marking of installation . 39
10.4.5 Additional measures to ensure ongoing risk mitigation . 39
11 Recommendation . 39
Annex A (informative) Risk analysis. 41
Annex B (informative) Segmentation of the industry sector . 88
Annex C (informative) Assessment of safety-related barriers to adoption . 94
Annex D (informative) Design measures . 99
Annex E (informative) Relevant Standards and Legislation used in this sector . 101
Annex F (informative) Review of work programmes . 105
Annex G (informative) Assessment of the way risk analysis is used. 110
Annex H (informative) Transport refrigeration . 130
Annex I (informative) Calculations and assumptions for section G.6 - Air conditioning and
heat pumps . 143
Annex J (informative) AREA CLASSIFICATION . 153
Bibliography . 155
European foreword
This document (CEN/TR 17608:2022) has been prepared by Technical Committee CEN/TC 182
“Refrigerating systems, safety and environmental requirements”, the secretariat of which is held by
DIN.
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.
Any feedback and questions on this document should be directed to the users’ national standards
body. A complete listing of these bodies can be found on the CEN website.
Introduction
CEN and CENELEC implemented standardisation request M/555 - IMPLEMENTING DECISION of 14
November 2017 on a standardisation request to the European Committee for Standardisation and to
the European Committee for Electrotechnical Standardisation as regards use of flammable refrigerants
in refrigeration, air conditioning and heat pump equipment. CEN/TC 182 took the lead and established
a liaison with CENELEC/TC 61.
The two European Standardization Organizations CEN and CENELEC have responded positively to
standardisation request M/555 regarding use of flammable refrigerants in refrigeration, air
conditioning and heat pump equipment.
CEN/TC 182 and CENELEC/TC 61 were tasked to address the standardisation request. A new working
group (WG12) was set up under CEN/TC 182 with active participation of experts nominated by
CENELEC/TC 61.
The technical information was gathered by six ad hoc groups two of which were led by CENELEC/TC 61
experts. The ad hoc groups analysed the current status of risk assessment in general, commercial
refrigeration, transport refrigeration, industrial refrigeration, air conditioning and heat pumps, and
chillers. Each of the groups finalized their summary with conclusions about existing barriers and
recommendations for additional options.
The Technical Committee reviewed guidance for the risk assessment in general and for refrigeration
appliances in particular. This includes reviews of guidance and standards that apply for flammable
gases in general. Also, the risk assessment was reviewed of global organisations like the risk approach
of the Organisation for Economic Co-operation, Development and United Nations Development
Programme and United Nations Environment Programme.
The requirements of the Standardisation Request M/555 were reviewed carefully. Having reviewed the
documentation, the working group agree that, responding to the standardisation request, the following
deliverables were to be prepared:
1) A Technical Specification for the installation of refrigeration, air conditioning and heat pump
equipment containing flammable refrigerants, complementing existing standards.
2) A Technical Specification for the operation, servicing, maintenance, repair and
decommissioning of refrigeration, air conditioning and heat pump equipment containing
flammable refrigerants, complementing existing standards.
The recommendations about transport refrigeration are beyond the standardisation request M/555.
CEN/TC 413 will develop of a specific EN standard dedicated to transport refrigeration risk assessment.
1 Scope
This document provides the results of a comprehensive assessment of the state of the art on the use of
flammable refrigerants, in particular from class A3.
Refrigerants from class B (toxic) are excluded from this scope.
This document includes the following elements:
• A segmentation of the refrigeration, air conditioning and heat pump market, making use of existing
studies and research, including an assessment of safety-related barriers to the uptake of flammable
refrigerants in particular from class A3 across all relevant applications;
• An assessment of the way risk assessments is used in existing standards for refrigeration, air
conditioning and heat pump equipment and in other standards and a review of available risk
assessment research to be taken into account including identification of potential needs for
additional research;
• Analysis of:
• the relationship between risk and increased charge;
• the acceptability of increased risk compared to the risk presented by other technologies;
• the options for additional mitigation methods if the risk increase is unacceptable;
• Review of existing standards and work programmes and identification of standards that should be
further updated under existing or future standardisation requests based on relevant product safety
legislation, in particular with regard to allowable charge sizes of flammable refrigerants, taking into
account available technology as well as emerging research and development;
• Identification of options for performance based requirements that result from risk assessments to
enable the use of all flammable substances;
• Identification of options for risk minimisation and for offering flexibility in application of mitigation
measures.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Segmentation of the Industry Sector
4.1 General
The refrigeration industry produces a wide range of products and applications. Commercial and
professional refrigeration, industrial refrigeration, chillers and air conditioning, transport refrigeration,
and heat pumps were investigated. The main results are reflected in this clause. The complete result of
the review is provided in Annex B.
4.2 Commercial applications
4.2.1 Commercial Refrigeration
Commercial refrigerated cabinets are used for storage, display, production, or sales of foodstuff. Some
of these products are fixed and movable appliances.
Commercial refrigerated cabinets are cooled by a refrigerating system which enables chilled and frozen
foodstuffs placed therein for display to be maintained within prescribed temperature limits.
Commercial refrigerators and freezers cover a large variety of products; and they are used in diverse
environments such as supermarkets, grocery stores, service stations, restaurants, hotels, pubs, and
cafés. Commercial Service Cabinets are mainly horizontal refrigerated display cabinets which requires
that a person serve the customer with fresh-cut or packed foodstuffs; and the appliance have one or
more side facing the customer for display of fresh cut of food in a supermarket. As a sub-category some
of these cabinets are also available as Self Service version.
Commercial refrigeration equipment can take many forms and combinations:
• ‘self-contained (or plug-in or integral) appliance’ means a factory made assembly of refrigerating
components that are an integral part of the refrigerated equipment and consists of a storage space,
one or more refrigerant compressors, refrigerant evaporators, condensers and expansion devices,
eventually accompanied with additional heat exchangers, fans, motors and factory supplied
accessories;
• remote display cabinets work with a remote refrigerating unit which is not an integral part of the
display cabinet (e.g. condensing units, cooling packs);
• semi plug-in cabinets are cabinets with an integral condensing unit, where the heat is rejected with
a secondary water or brine loop;
• refrigerating system with secondary fluid (e.g. chillers).
4.2.2 Professional Refrigerated Products
Professional refrigeration equipment can take many forms and combinations, very similar to those for
commercial use. Professional service cabinets are designed for dispensing or storage, but not the sale, of
chilled and frozen foodstuff like professional storage cabinets, blast chillers, cold rooms, ice cream
makers, etc. A professional service cabinet is a refrigerated enclosure containing goods which are
accessible via one or more doors and/or drawers. The sizes of the products are typically based on the
standard tray and are used in a commercial environment. They are largely used in foodservice
establishments, such as restaurants, hotels, and cafeterias. A very small fraction of “professional”
service cabinets contain glass in their doors, drawers, or lids (as opposed to “commercial” service
cabinets that display food and hence frequently incorporate glass).
Blast cabinets use a blast of cold air to bring down the temperature of hot food rapidly so it can be
stored safely avoiding bacteria growth, and can be chilled or frozen. Blast cabinets are similar in
construction to service cabinets. However, they rely on relatively larger refrigeration systems in
comparison to service cabinets, some even using up to two compressors per cabinet. Blast cabinets also
contain additional fans which blast cold air over food to cool it rapidly.
4.2.3 Commercial versus professional cabinets
Both commercial and professional cabinets rely on compression technology (more than 90%): i.e. all
components supporting the refrigeration cycle are included in the cabinet.
The main difference between commercial and professional is not related to installation environment,
but to the user: a “commercial” refrigerator is used by a customer (shopper), and will display products,
while a “professional” refrigerator is used by trained staff, and will store the products before use.
Frequently existing definitions refer to “commercial” service cabinets, when in fact “professional” use of
the products is done one side of the appliance, while the other side is for display or collection of product
from the shopper that could access a side of the appliance. Therefore, it is noted that terminology varies
for identical products.
4.3 Industrial applications
Industrial systems are characterized primarily by the size of the equipment, both physical size and heat
transfer capability, and the temperature range covered by the sector. In addition to Industrial
Refrigeration, this sector includes Industrial Heat Pumps (heating systems similar in scale and
application to Industrial Refrigeration systems) and Industrial Air Conditioning (systems for controlling
air temperature in production factories, computer centres and other process areas). Other sectors
mainly focus on comfort and food, the industrial sector also includes refrigerating systems for process
related activities, example temperature controls in in chemical processes.
Industrial Refrigeration systems are characterized by heat extraction rates in the range 100 kW to
10 MW, typically at evaporating temperatures from – 50 °C to + 20 °C. There is some overlap at the
lower end of the capacity scale with commercial refrigeration for shops, restaurants, and institutions.
Industrial systems in this sub-sector are characterized by the complexity of the design and the nature of
the installation. Systems at lower temperatures, typically down to – 120 °C, and in capacity ranges from
1 kW to 200 kW are a specialized sub-sector including laboratory equipment for pharmaceutical,
chemical, and medical applications and test stands for automotive, aerospace and space development
facilities. These ultra-low temperature systems are often also required to operate at high temperatures
up to + 250 °C to provide a complete temperature test cycle.
Industrial Heat Pump systems have heat delivery rates from 100 kW to over 100 MW, with the heat
source usually at ambient temperature or the waste heat temperature of an industrial process. These
systems are usually required to deliver higher temperatures than domestic or commercial heat pumps
used for space or water heating. Typical temperatures are in the range 60 °C to 90 °C, although if the
recovered heat is to be used for steam raising then it needs to be at least 120 °C. Heat recovered from
large industrial systems is usually transferred to water or a heat transfer fluid and used for process
heating or for supply to district heating systems.
Industrial Air Conditioning systems cannot be differentiated from commercial systems on size alone, as
many commercial office buildings have large cooling loads. In addition to size of installation the
distinguishing traits of Industrial Air Conditioning systems are that the cooling is not purely for human
comfort, the load is not primarily seasonal, and the operation of the facility would be jeopardized by
failure of the cooling equipment. Such systems are sometimes called “Mission Critical” and have special
design requirements, including the need for uninterrupted service, which are not typically provided by
traditional heating, ventilation, and air conditioning practices. In some cases, the mission-critical part of
a total cooling load may be supplied in conjunction with a comfort cooling system, configured so that, in
the event of partial failure of the system, the mission-critical cooling is maintained at the expense of the
comfort of the occupants of the rest of the building. Other Industrial Air Conditioning systems are
primarily required to maintain acceptable processing conditions for equipment such as computer
servers in data centres.
4.4 Chillers and heat pumps with water heat sink, indirect systems
Chillers and heat pumps with water heat sink are used in domestic, commercial, professional, and
industrial applications. Chillers and heat pumps with water heat sink include units with a refrigerant to
water heat exchanger on the use side. Capacity range is from about 1 kW up to 2 000 kW.
The units are air to water heat pumps self-contained, water to water heat pumps self-contained, brine
to water heat pumps self-contained, air to water heat pumps split, chillers and domestic hot water heat
pumps.
The products are used in all market segments. The overall market is 800 000 units per year.
4.5 Air to air air conditioning and heat pumps
Domestic air conditioning products and domestic heat pumps are used in households and similar
locations for cooling and heating applying air conditioners and heat pumps. This application category
also includes similar applications like care homes, retirement homes and other facilities with nursing
services.
Air conditioners generally fall into several distinct categories, based primarily on capacity or
application: small self-contained air conditioners, such as window-mounted and through-the-wall air
conditioners; non-ducted split residential and commercial air conditioners; ducted, split residential air
conditioners; and ducted commercial split, multi-split including variable refrigerant flow, and packaged
air conditioners. In each of these categories, the term “air conditioner” includes systems that directly
cool or heat the conditioned air, for instance, “air-to-air”, “water-to-air” and “ground-to-air” systems.
This category does not include systems that heat or cool water or other heat transferring liquids.
NOTE For example, through the wall; whilst these products represent a small portion of the market they have
nevertheless been included since they are still available and have certain construction characteristics of interest.
Packaged terminal air conditioner are not usually used in Europe.
Table 1 summarizes the typical physical and installation characteristics of the different types of air
conditioners.
Table 1 — Typical configurations of air conditioner types
Capacity R-410A
Type Primary configuration System layout range charge
(kW) range (kg)
double duct Small self-contained Self-contained 1 – 10 0.3 – 3
Hermetically-
sealed unit a
single duct Small self-contained Self-contained 1 – 10 0.3 – 3
Duct free split Ducted free split Remote 2 – 20 0.5 – 6
Multi-split including variable
Multi-split Remote 4 – 300 1 – 80
refrigerant flow
Residential/small cap Remote 4 – 20 1 – 6
Ducted split
Commercial/large cap Remote 10 – 150 3 – 45
b
Packaged rooftop Ducted commercial Self-contained 7 – 350 2 – 100
Exhaust air-to-air heat pump Inside / outside Self-contained 5 – 150 1.5 – 45
a
Single duct is used to refer to portable air conditioners.
b
Generally these products are designed with 2 circuits. That is to say 100 kg for the complete unit 350 kW will
give 50 kg per circuit.
4.6 Transport applications
The transport applications market distinguishes between human comfort and transport of refrigerated
goods. Transport applications includes mobile air conditioning systems in vehicles, railways, buses,
vans, mobile homes and caravans for human comfort; and, for the transport of refrigerated goods
refrigerated trucks, trailers and reefer containers land-based operation.
Transport applications have specific challenges such as shock, vibration, corrosion, and extreme
operating ambient conditions. This leads to design choices different from other refrigeration
applications.
Transport of refrigerated goods is typically a non-occupied area with limited access, with periodic, or
non-frequent access by humans. The refrigeration units are factory built and typically mounted onto the
actual vehicles, casing, or chassis.
Some systems use open type compressors with shaft seals and are driven by the main engine, for
example car bus air conditioning with combustion engines. Other systems operate with hermetic or
semi-hermetic compressors and electric power supply.
The United Nations Environment Programme Refrigeration and Air Conditioning Technical Options
Committee (RTOC) 2018 report stated: “Light duty vehicles use from 0,3 kg to 1,4 kg refrigerant charge,
while for buses the charge could be from 8 kg up to 16 kg as a function of the vehicle category (e.g.
simple bus, articulated bus). Currently there are approximately 1 000 kt of refrigerant in vehicles
considering that there are about 1,3 billion of road vehicles circulating . Assuming that 75 % of
circulating vehicles is equipped with mobile air conditioning systems, and assuming a yearly renewal
rate of 8 % e.g. 100 million units), the refrigerant demand (excluding service) is about 75 kt/year.”
5 Current practice in the sector
All substances that exist in liquid and vapour states absorb heat during evaporation and can therefore
be used as refrigerants. Refrigerants have widely varying properties and impacts and due to the
significant environmental and safety impact of certain refrigerant types, can be heavily regulated during
manufacture, use and disposal. There are numerous refrigerants either in use today or being proposed
as alternatives. Commonly used refrigerants in refrigeration applications are the following:
• HFCs: Hydrofluorocarbons
• HCs: Hydrocarbons
• Unsaturated HFCs (also known as HFOs or Hydrofluoroolefins)
• NH3: Ammonia
• CO2: Carbon dioxide
Table 2 lists the various options that are currently in use or under consideration for air conditioning,
along with their global warming potential and ISO 817 safety classification. Also listed are the types of
air conditioner system that each refrigerant option is currently used in or is at least being considered
for. All options listed are toxicity class A.
https://www.statista.com/statistics/281134/number-of-vehicles-in-use-worldwide/.
Table 2 — Refrigerant options for air conditioning
GWP Subsector currently
Flammability Subsector proposed/
Refrigerant (RTOCa used in the European
class anticipated
2018) Union
R-1270 < 1 3 non ducted system
R-290 small self-contained, ducted commercial split
< 1 3 ducted split,
packaged rooftop
R-1234yf < 1 2L small self-contained
R-152a 148 2 non ducted system
R-32 small self-contained, multi-split,
non ducted system, packaged rooftop
704 2L
ducted split,
ducted commercial split
R-452B 710 2L All
R-454A 250 2L All
R-454B 490 2L All
R-459A 480 2L All
a
United Nations Environment Programme Refrigeration and Air Conditioning Technical Options Committee.
Currently the majority of commercial plug-in or self-contained refrigeration appliances using flammable
refrigerants have charge sizes of no more than 150 g of hydrocarbon (HC) such as R-600a (isobutane)
or R-290 (propane) per refrigerant circuit. This is due to the charge size constraint of 150 g of
flammable refrigerant within the current IEC 60335-2-89 Ed. 3. There are several millions of such units
currently in use.
Horizontal standards such as EN 378 (2016) and ISO 5149 (2014) permit charge sizes of up to 1,5 kg of
hydrocarbon per refrigerant circuit. Where the charge exceeds 150 g there are additional requirements
for the installation site, such as certain minimum room size in which the system can be placed, a
mandatory risk assessment considering the specific installation surroundings due to the potential
higher charges released, a plant by plant certification.
Whilst the number of self-contained refrigeration appliances using flammable refrigerants is relatively
minor compared to global populations of self-contained refrigeration appliances with non-flammable
refrigerants, there is reasonably good level of experience with such self-contained refrigeration
appliances and especially with products using up to 150 g per circuit. If there was a fundamental
underestimation of the risk posed by the current design requirements for these self-contained
refrigeration appliances, then this would become apparent to the direct stakeholders and the industry
as a whole. Based on this historical data the use of flammable refrigerants with a maximum charge of
150 g per circuit in self-contained refrigeration appliances can be considered as an acceptable risk.
Recent regional and international legislation such as the European F-gas regulation, the 2016 Kigali
Amendment of the Montreal Protocol and minimum efficiency regulations in USA and other countries
mean that most common refrigerants used today in self-contained refrigeration appliances will no
longer be applicable. Apart from R-744, the only viable refrigerants for the short to medium term are
flammable, and even out of the possible options only a small number of hydrocarbons and
hydrofluorocarbon/u-hydrofluorocarbon mixtures may be viable.
Based on this historical data the use of flammable refrigerants with a maximum charge of 150 g per
circuit in self-contained refrigeration appliances can be considered as an acceptable risk without taking
care of surrounding environment using a safety approach based on type tests.
Chillers only connected by a secondary system to the area served the appliance can be positioned
outside or be equipped with ventilated enclosure / machinery room that allows to handle even high
refrigerant charges safely.
Large refrigeration systems often use R-717 (ammonia) as the refrigerant. R-717 is classed as B2L by
the ISO 817 safety classification. Where R-717 is considered to be unacceptable the decision is usually
based on the hazards posed by toxicity in the specific location, for example if the system is located in a
built up area or close to a school or hospital. The most likely alternative until recently would have been
a non-flammable, lower toxicity refrigerant such as R-404A or R-507. As these are being phased out due
to high global warming potential there is an increased interest in R-744 (carbon dioxide) either in
cascade with R-717 or in a transcritical system configuration. There is currently virtually no use of A3
refrigerants in the industrial sector except in specialist niche markets where the flammability of the
refrigerant is not an additional concern, for example in a process plant or oil refinery.
6 Design measures for flammable refrigerants
6.1 General
Products placed onto the European single market satisfy the requisite health, safety, and environmental
requirements. How this is achieved is laid out in the 'Blue Guide' on the implementation of EU product
rules 2016. It is necessary to meet the essential health and safety requirements of the applicable
European Directive or Directives in order to place a product on the market. Detailed design measures
are given in Annex D.
Following a harmonized standard is an easy way to comply with the requisite essential health and
safety requirements. If other routes are used, they may be depending upon the applicable directives and
the necessary conformity route. A notified body may have to verify the approach. Figure 1 gives an
explanation of the routes that are appropriate for meeting the essential health and safety requirements
of Directives. Provided that the essential health and safety requirements of the relevant Directives are
satisfied, then following any or no European refrigeration, air conditioning and heat pump safety
standards are permitted.
Figure 1 — The role of harmonized standards when complying with applicable essential
requirements identified by a manufacturer
Regardless whether harmonized standards are followed to comply with the essential requirements of
the regulations, a risk assessment of the product has to be performed as required by the regulations
pertaining to safety.
6.2 Design measures
Figure 2 provides an overview of the various levels of intervention that may be applied to refrigeration,
air conditioning and heat pumps systems and equipment, along with some examples of how these
interventions may be practically applied. Broadly, those at the top of the list can be considered as
having a higher level of reliability. As a priority, those measures that avoid the refrigerant entering into
the space may be deemed more reliable, whereas those which require intervention of human occupants
to initiate some action to reduce the risk may be deemed less reliable. Thus, the approaches towards the
top of the list may be considered preferentially, although this can also be affected by specific
circumstances and equipment type.
Figure 2 — Overview of preventative measures and practical examples applicable to
refrigeration, air conditioning and heat pump systems
The following are the basic considerations that typically apply to flammable refrigerants, all of which
should be integrated into any installation:
• No sources of ignition
• Ensuring system tightness
• Limiting refrigerant charge
• Warnings/marking
• Instructions
These measures are in addition to others related to pressure and mechanical safety.
Amongst the following there are measures that are applied to A2L refrigerants but not to A2 and A3
refrigerants. The measures should be considered for all flammable refrigerants.
a) Basic measures
The following are the basic considerations that typically apply to flammables, all of which should be
integrated into any one system/installation:
• No sources of ignition
• Ensuring system tightness
• Limiting refrigerant charge
• Warnings/marking
• Instructions
• Markings
A variety of other measures have recently been introduced into various refrigeration, air conditioning
and heat pump safety standards.
For air conditioners, applicable measures include (either individually or in combination):
• Room size limitation
• Ventilated enclosure
• Gas detection and extract ventilation (for machinery rooms)
• Circulation airflow (continuous or initiated by gas detection)
• Improved system tightness
• Reliance upon natural ventilation openings to dilute leaked refrigerant
• Use of shut-off valves to limit charge being released
• Gas detection and alarm
• Gas detection and extract ventilation (for occupied rooms)
There are a number of other measures that are either currently in use by manufacturers or suggested
within the literature or both. Many such measures could be useful for extending the safe application of
flammable refrigerants across air conditioner subsectors.
• Design of enclosures or housings to better dilute releases
• Alternative means of leak detection, for example system parameters, ultrasonic, flash gas
indication
• Limiting releasable charge
• Circulation airflow, either continuous or initiated by detection
• Improved system tightness
• Use of shut-off valves to limit charge being released
• Gas detection and ventilation for occupied rooms
• Surrounding concentration test
NOTE Surrounding concentration test is currently proposed for commercial refrigeration appliances under
IEC 60335-2-89.
Table 3 provides an overview of protective measures within published refrigeration, air conditioning
and heat pump safety standards.
Table 3 — Applicable clauses on protective measures within refrigeration, air conditioning and
heat pump safety standards
a
Measure IEC 60335-2-89: IEC 60335-2-40 EN 60335-2-40 EN ISO
2019 378 5149
No sources of 22.111.1 22.116, 22.117 22.116 Part 2, Limited
ignition 6.2.14
22.112
22.113
Annex BB
Ensuring system 22.119 22.113 n/a Part 2 Part 1
tightness A5;
22.120
Part 2
Limiting refri
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