Hydrocarbon Refrigerants TrainingPresented by

Refrigeration Service

Engineers Society

1. Uses of Hydrocarbons as Refrigerants

2. HC Regulations and Standards

3. Refrigerant Properties and Safety

4. The Refrigerant Cycle

5. System Components

6. Servicing Procedures

Topics to Cover

• 1900’s - HCs used in infancy of the refrigeration industry;• 1930’s - CFCs developed (non-flammable), HC use

reduces;• 1970’s - Ozone depletions by CFCs discovered;• 1980 - HFC and HC start to replace CFCs;• 2000 - Launch of HC ice cream cabinets;• 2005 - Over 50,000 HC cabinets in use in Europe.

History of Hydrocarbons as Refrigerants

Must follow recommended safety practices when working with these approved flammable refrigerants

R-600a-IsobutaneR-290-Propane R-441A-Flammable blend

Why use Flammable Refrigerants?

The Montreal ProtocolReduces CFC and HCFC Production

EPA Approves Use of HCs through the Significant New

Alternatives Policy (SNAP)

Low Global Warming Potentials (GWP) Less than 3

Zero Ozone DepletingPotential (ODP)

Technician servicing procedures need to change with the introduction of flammable refrigerants

• HCs already used worldwide;• Over 80 million domestic refrigerators in use worldwide;• HCs also used in commercial appliances-bottle coolers, chest freezers,

commercial refrigerators;• Also used in split system and portable AC systems in use, however not

yet approved in USA

• R-600a and R-441A – New Household Refrigerators and Refrigerator/Freezers-57 grams (2.0 ounces) Equipment Constructed following UL250-Current Edition

• R-290 – New Retail Food Refrigerators Freezers-150 grams (5.3 ounces) Equipment Constructed following UL471-Current Edition

Applications and Limits

R-600a-IsobutaneR-290-Propane R-441A-Flammable blend

Common Regulator AgenciesEPA NFPA

CSA EC

ISO IEC

ASHRAE UL

Ultimately the technician is responsible for knowing the local regulations

Understanding HC Regulations

Keeping Up with Regulations

http://www.epa.gov/ozone/snap/regulations.html

• HCs allowed for use in only new systems under the SNAP approved program;

• NO RETROFITTING allowed in the USA (retrofitting is allowed in other countries).

Unauthorized Applications

• Before servicing equipment look for MATCHING refrigerants equipment labels (the unit and compressor)

• If the compressor and refrigerant match then it should be acceptable to service the system

• If the labels do not match assume the system has been retrofitted and– STOP work on this system immediately– Contact the owner– Inform owner of system violations– Refuse to service– Offer to replace system with approved systems

Unauthorized Refrigerants

• Be an qualified refrigeration technician;• Be familiar with the safety precautions for flammable refrigerants;• Be familiar with the information provided by other sources, such as the

manufacturers of the system equipment, component manufacturers, and refrigerant suppliers.

EPA Further Information Statement

Identification Labeling

• Compressors and systems will have labels identifying the type of flammable refrigerant.

• UL 250 and 471 require labeling as part of the SNAP approval

"DANGER- Risk of Fire or Explosion. Flammable Refrigerant Used. Do Not Use Mechanical Devices To Defrost Refrigerator. Do Not Puncture Refrigerant Tubing."

Further Labeling Requirements

Labeling attach on or near any evaporators

Evaporator Labeling Requirements

"DANGER- Risk of Fire or Explosion. Flammable Refrigerant Used. To Be Repaired Only By Trained Service Personnel. Do Not Puncture Refrigerant Tubing."

Further Labeling Requirements

Attach near the machine/compressor compartment

Machine/Compressor Labeling Requirements

“CAUTION- Risk of Fire or Explosion. Flammable Refrigerant Used. Consult Repair Manual/Owner’s Guide Before Attempting To Service This Product. All Safety Precautions Must be Followed."

“CAUTION- Risk of Fire or Explosion. Dispose of Properly In Accordance With Federal Or Local Regulations. Flammable Refrigerant Used."

Further Labeling Requirements

Attach on the exterior of the refrigerator

Exterior Labeling Requirements

“CAUTION- Risk of Fire or Explosion Due To Puncture Of Refrigerant Tubing; Follow Handling Instructions Carefully. Flammable Refrigerant Used."

Further Labeling Requirements

Attach near any and all exposed refrigerant tubing

Near Refrigerant Tubing Labeling Requirements

All of these markings shall be in letters NO LESS than 6.4 mm (1/4”) high.

Further Labeling Requirements

“CAUTION- Risk of Fire or Explosion Due To Puncture Of Refrigerant Tubing; Follow Handling Instructions Carefully. Flammable Refrigerant Used."

Letter Sizing

• The refrigerator or freezer must have red, Pantone® Matching System (PMS) #185 marked pipes, and other devices through which the refrigerant is serviced, such as any service port;

• This color must be present at all service ports and where service puncturing or otherwise creating an opening from the refrigerant circuit to the atmosphere might be expected (e.g., process tubes).

• The color mark must extend at least 2.5 centimeters (1”) from the compressor and must be replaced if removed, repaint if necessary

Further Labeling Requirements

Service Access &Tubing Painting

• Working with any refrigerant carries a certain liability• Check with your insurance carrier before with HC refrigerants

Liability

      SAFETY GROUP

Increasing Flammabili

ty 

Higher Flammability A3 B3Lower Flammability A2 B2

A2L* B2L*No Flame Propagation A1 B1

      Lower Toxicity

Higher Toxicity

           Increasing Toxicity

A2L and B2L are lower flammability refrigerants See ASHRAE Standard 34 for full Details Refrigerant Safety Group Classification

ASHRAE Refrigerant Ratings

Sudden release of refrigerant can result in proper concentrations for:

Flash Fire • Sustained Fire • Explosion

Flammability and Ignition

• Temperatures greater than 460°C or 860°F;• Flame from a match;• Torch including halide leak detectors.

Ignition Sources

Electric sparks from:• Light and Socket Switches• Unsealed Relays and Overloads• On Off switches• Contactors• Pressure Switches• Defrost Timers• Thermostats• Vacuum Pump Switches• Electronic Leak Detectors

Ignition Sources

LEL -Lower Explosive Limits

R290-2.1%

R600a-1.8%

UEL-Upper Explosive Limit

R-290-9.5%

R600a-8.5%

Upper and Lower Explosive (Flame) Limits

Material Safety Data Sheets• Required to be availability to

all employees• Also required to be available

to local Fire Departments

MSDS

CHECK WITH THE AUTHORITY HAVING JURISDICATION (AHJ) FOR LOCAL REGULATIONS

• Never store or expose to temperatures above 125°F (52°C);• Never apply open flame;• Never heat with water or heat blanket above 110°F (43°C);• Never refill single trip cylinders;• Never exceed refillable limits;• Never remove labels;• Never smoke near flammable refrigerant cylinders.

Cylinder Safety

• Department of Transportation Division 2.1 Classification-Flammable Gas– Transport in upright position– Label vehicle as carrying flammable gas– Inventory vehicle contents

• Some jurisdictions require– Storage in explosive proof cabinets– Venting of cabinet to exterior

Check the local Authority Having Jurisdiction

Cylinder Transport

• Store in a locked cage;• Store at ground level;• Store away from air intakes;• Keep ignition sources away

from area;• Limit access;• Install combustible gas

monitors.

Cylinder Storage

Check the local Authority Having Jurisdiction

• Recover refrigerant;• Ventilate the area;• Wear personal protection

equipment (PPE);• Check brazing equipment for

leaks and proper pressure settings;

• Purge with inert gas while brazing (Nitrogen);

• Only trained and qualified personal should be brazing.

Brazing Requirements

• Flammable gas leak detectors and monitors;• Personal safety monitors.

Rated Equipment

All refrigerants in confined space have inherent dangers.

Remember to:• Use a combustible gas detector and /or monitor• Ventilate area and clear the area of any potential LEL or

UE;• Eliminate alll sources of ignition

Confined Space

Basic cycle is the same as it is for CFCs, HCFCs, & HFCs

Refrigerant Cycle

What is different• Additional safety requirements• Monitor area and prevent possible ignition sources• Ventilate area when required• Using tubing cutting to remove refrigeration components – do

not use a torch

Refrigerant Cycle

Generally Same Components UsedCondenser Evaporator Metering Device Lubricants Gaskets,

Seals, O-rings

Refrigerant Cycle

Always Use Approval Components When Replacing

• Use only spark proof equipment-like a brass screwdriver,• Use non-ignitable type detectors such as UV additive, liquid detection

solution, electronic leak detectors for flammable gasses or ultra sonic leak detectors

Servicing Procedures

• Use standard evacuation and pressure testing procedures• Use standard recovery methods• Use standard charging methods (weigh in)

Servicing Procedures