Thanavat Junchaya WB ISO 5149 Dominican Republic Presentation Thanavat

Annual Joint Network Meeting of National Ozone Officers of Latin America and the Caribbean, The Dominican Republic 2-5 December 2014

ISO 5149 Impact on RAC Installation and Servicing Thanavat Junchaya Implementing Agency Coordination Unit

International Standard ISO 5149

Refrigerating systems and heat pumps Safety and environmental requirements

First Edition 2014-04-15 replaces ISO 5149:1993

The revision was promoted by entry of new refrigerants and blends in the market and the introduction of new safety classifications

Consists of the following parts:

Part 1: Definitions, classification and selection criteria;

Part 2: Design, construction, testing, marking and documentation;

Part 3: Installation site; and

Part 4: Operation, maintenance, repair and recovery

2

Refrigerant Safety Classification

Safety Group

Higher flammability

A3 B3 LFL 0.1 kg/m3 or HC 19 MJ/kg

Lower flammability

A2 B2 LFL > 0.1 kg/m3 and HC < 19 MJ/kg

A2L* B2L*

No flame propagation

A1 B1

Lower Toxicity PEL > 400 PPM

Higher Toxicity PEL < 400 PPM

* Maximum burning velocity 10 cm/s

3

Low-GWP Alternatives & Refrigerant Safety Classification GWP A1 A2 A2L A3 B2L

3,001 CFC-12, R-404A

HFC-143a

4

Part 1 of ISO 5149:2014 Definition, classification and selection criteria

This part applies to:

Refrigerating systems, stationary or mobile (except vehicle air conditioning systems) of all sizes including heat pumps;

Secondary cooling or heating systems;

The location of the refrigerating systems;

New systems, extensions or modifications of any existing systems, and for used systems, being transferred to and operated on another site, as well as in the case of the conversion of a system to another refrigerant.

5

Refrigerant Charge Limit

ISO 5149 determines refrigerant charge limit of refrigerating systems depending on:

Occupancy classification;

Location classification of refrigerating systems;

Specific toxicity and flammability characteristics of the refrigerant used

The charge limit can be an absolute value or calculated from characteristic refrigerant data and room volumes

6

Occupancy Classification

General occupancy a (hotels, schools, restaurant) Rooms, parts of building where any person has access without being personally acquainted with the necessary safety precautions;

Supervised occupancy b (offices) Rooms, parts of buildings, buildings where only a limited number of people can be assembled, some being necessarily acquainted with the general safety precautions of the establishment;

Authorized occupancy c (manufacturing facilities) Rooms, parts of buildings, buildings where only authorized persons have access, who are acquainted with general and special safety precautions of the establishment and where manufacturing, processing, or storage of material or products take place.

Note: Machinery rooms shall not be considered as an occupied space except as defined in ISO 5149-3: 2014, 5.1.

7

Location Classification of Refrigerating Systems

Class I: mechanical equipment located within the occupied space the refrigerating system or refrigerant-containing parts are located in the occupied space;

Class II: compressors in machinery room or open air all compressors and pressure vessels are either located in a machinery room or in the open air; coil-type heat exchangers and pipework, including valves, can be located in an occupied space;

Class III: machinery room or open air all refrigerant-containing parts are located in the machinery room or open air. The machinery room should fulfil the requirements of ISO 5149-3; and

Class IV: ventilated enclosures all refrigerant-containing parts are located in the ventilated enclosures.

8

Charge Limit Requirements for A2L Refrigerant

9

Charge Limit Requirements for A3 Refrigerant

10

Method to Determine Charge Limit of a Refrigerating System

1. Define which occupancy category (a, b, or c) applies and which location class (I, II, III, or IV) the system is used in

2. Define the toxicity class of the refrigerant (A or B)

3. The toxicity limit equals ATEL/ODL values or practical limits whichever is higher

4. Determine the charge limit (toxicity)

5. Define the flammability class of the refrigerant (1, 2L, 2, 3, etc.) used in the refrigerating system and the corresponding LFL

6. Determine the charge limit (flammability)

7. The lowest refrigerant charge obtained according to 3) and 5) is applied

11

Case Study

Occupancy

Our interest is in residential air-conditioning system which can be installed in home or offices; hence, general occupancy/human comfort is considered as it establishes a conservative baseline.

Location of refrigerating systems

Classes I and II which are applicable for unitary and split systems are considered in details; and

Classes III and IV which are applicable for larger air-conditioning systems will be touched on briefly.

Refrigerant

R-32 is considered as an example for A2L materials; and

R-290 is considered as an example for A3 materials.

12

CAP Factor

The charge limits in are capped to a limit based upon the LFL of the refrigerant.

In the case of flammability class 2 or 3 refrigerants, the basic cap factor is m1, m2, and m3.

For flammability class 2L refrigerants, the basic cap factor is increased by a factor of 1.5 due to lower burning velocity

There are no room volume restrictions for refrigerant charges below or equal to m1

Cap Factor R-32 (kg) R-290 (kg)

m1 = 4 m3 x LFL 1.8* 0.15

m2 = 26 m3 x LFL 12* 1.0

m3 = 130 m3 x LFL 60* 5.0

13 * Increased by a factor of 1.5

For AC with Refrigerant-Containing Parts used for Human Comfort and Charge > m1

Charge limits are determined by:

= 2.5 5/4

1/2

where:

14

mmax allowable maximum charge in a room (kg)

m refrigerant charge amount in the system (kg)

A room area (m2);

LFL Lower Flammability Limit (kg/m3);

h0 height factor based upon the method of mounting the appliance (m)

Note: floor: 0.6m, window: 1.0m, wall: 1.8m, ceiling:2.2m

Maximum Charge Limit for HFC-32 AC used in Class I or II location for human comfort

15

Comparison of Maximum Charge Limit between R-32 and R-290 Wall-Mounted AC

16

Cooling Load and Impact from ISO 5149 Charge Limit

Cooling Load Estimate

Basic Assumptions

Room size = 30 m2

Cooling load = 600 BTU/hr/m2 (175 W/m2)

Cooling requirement = 18,000 BTU/hr (~3.5 kW)

Estimate refrigerant charge for 18,000 BTU/hr AC:

R-290 (@ 0.3 kg/RT) = 0.45 kg

R-32 (@ 0.7 kg/RT) = 1.05 kg

ISO 5149 Charge Limit

Mounted locations

R-290 R-32

Floor 0.15 1.88

Window 0.23 3.13

Wall 0.41 5.73

Ceiling 0.51 6.88

17

Conclusions (I)

For residential a/c systems

R-32:

for charge size (m) less than 1.8 kg, there are no restrictions;

for 1.8 kg

Conclusions (II)

For Classes III and IV (chillers)

R-32:

No charge size restrictions for Class III for which all refrigerant-containing parts are installed in a machinery room with mechanical ventilation or in open air;

Charge size should not exceed 60 kg if all refrigerant-containing parts are installed in ventilated area (Class IV) where no mechanical ventilation.

R-290

Charge size should not exceed 1 kg in case the machinery room is below ground, 5 kg in case the machinery room is above ground;

Charge size should not exceed 5 kg in case all refrigerant-containing parts are installed in ventilated area.

For supervised occupancy area, the charge size could increase to 10 kg; and for authorized occupancy area with a machinery room or open air located above ground, there is no charge size restriction, however, measures prescribed in ISO5149-3 must be applied.

20

Impact on RAC Manufacturing, Installation, and Servicing

Safety measures must be put in place properly at the manufacturing facilities;

Proper care is needed for transport of refrigerant and final products;

Installation must be done by qualified technicians and must be in compliance with local regulations and standards;

Servicing must be performed by well trained technicians most challenging task as it involves behavior changes;

Public must be aware of the need to have well trained technicians operating on their RACs. However, public education must be done strategically; otherwise, it may lead to adverse repercussion;

Flammable nature of new refrigerant also provides opportunities for upgrading the service industry. 21

Thank you

22