HFC134a Service Information

HFC134a is alternative refrigerant for CFC12. HFC134a has an ozone depletion potential (ODP) factor of 0.0 and a global warming potential (GWP) factor of 0.27. HFC134a is not flammable and has acceptable toxicity levels. HFC134a is not interchangeable with CFC12. There are significant differences between HFC134a and CFC12 which must be considered when handling and processing refrigeration system.

Health, Safety, and Handling

Health, safety and handling considerations for HFC134A are virtually no different than those for CFC12.

Health, Safety, and Handling

CFC12

HFC134a

 

 

 

Allowable overall exposure limit

1,000 ppm

Same

Vapor exposure to skin

No effect

Same

 

 

 

Liquid exposure to skin

Can cause frostbite

Same

Vapor exposure to eye

Very slight irritant

Same

Liquid exposure to eye

Can cause frostbite

Same

 

 

 

Above minimum exposure limit

Can cause Asphyxiation,

Same

 

Tachycardia, and Cardia

 

 

Arrhythmias

 

Safety and handling

Wear appropriate skin and eye

Same

 

protection. Use with adequate

 

 

ventilation.

 

Spill management

Remove or extinguish ignition or

Same

 

combustion sources. Evacuate

 

 

or ventilate area.

 

Fire and explosion hazards

May decompose if contact with

 

 

flames and heating elements.

 

 

Container may explode if heated

 

 

due to resulting pressure rise.

 

 

Combustion products are toxic.

 

Storage conditions

Procedures/rules for CFC12

Same

 

also apply for HFC134a

 

Disposal procedures

Recycle or reclaim

Same

 

 

 

Comparison of CFC12 and HFC134a Properties

Properties/Characteristics

CFC12

 

HFC134a

 

 

 

 

Ozone Depletion Potential (ODP)

1.0*

 

0.0*

Global Warming Potential (GPW)

3.2*

 

0.27*

Molecular weight

121

 

102

 

 

 

Boiling point at 1 atmosphere

-22°F (-30°C)

-15°F (-26°C)

Vapor pressure at 77°F (25°C)

80 psig

 

82 psig

Liquid density at 77°F (25°C)

82 lb/ft3

 

75 lb/ft3

Flammability

No

 

No

High-side system operating

HFC134a approximately 3 psig

Pressure at 65°F (18°C) ambient

higher than CFC12

Low-side system operating

HFC134a approximately 2 psig

Pressure at 65°F (18°C) ambient

lower than CFC12

 

* Compared to CFC 11 = 1

 

 

 

Caution

To minimize contamination, exercise extreme care when servicing HFC134A sealed systems.

No trace of other refrigerants is allowed in HFC134a systems. Chlorinated molecules in other refrigerants such as CFC12, etc. will lead to capillary tube plugging.

Ester oil is used in HFC134a systems. Do not use mineral oil. HFC134a and mineral oils cannot be mixed. If mineral oils were used in HFC134a systems, lubricant would not return to compressor and would cause early compressor failure. If significant amount of oil has been lost from compressor, replace oil rather than adding oil.

Ester oils used in HFC134a systems are so hydroscopic that by the time an inadequate system performance is detected, oil will be saturated with moisture.

CFC12 has much higher tolerance to system processing materials, such as drawing compounds, rust inhibitors, and cleaning compounds, than HFC134a. Such materials are not soluble in HFC134a systems. If materials were to be washed from system surfaces by ester oils, they could accumulate and eventually plug capillary tube.

Care must be taken to minimize moisture from entering HFC134a system. Do not leave compressor or system open to atmosphere for more than 10 minutes. Excessive moisture in HFC134a system will react with compressor oil and generate acid.

Compressor must be replaced when performing low side leak repair.

Drier filter must always be replaced with service drier filter, part #B2150504.

Important: Unbrazing drier filter from tubing will drive moisture from desiccant and into system, causing acids to form. Do not unbraze filter drier from tubing. If CFC12 service drier was installed in HFC134A system, drier could overload due to excessive moisture.

• HFC134a compatible copper tubing, part #R0174075 (1/4" O.D. X 18" length) and part #R0174076 (5/16" O.D. X 24" length) must be used when replacing tubing.

Avoid system contamination by using Towerdraw E610 evaporating oil, part # R0157532, when flaring, swaging, or cutting refrigeration tubing.

November 1996

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RS1200001

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Amana Bottom Mount Refrigerator service manual HFC134a Service Information, Health, Safety, and Handling