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 |
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Allowable overall exposure limit | 1,000 ppm | Same |
Vapor exposure to skin | No effect | Same |
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Liquid exposure to skin | Can cause frostbite | Same |
Vapor exposure to eye | Very slight irritant | Same |
Liquid exposure to eye | Can cause frostbite | Same |
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Above minimum exposure limit | Can cause Asphyxiation, | Same |
| Tachycardia, and Cardia |
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| Arrhythmias |
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Safety and handling | Wear appropriate skin and eye | Same |
| protection. Use with adequate |
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| ventilation. |
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Spill management | Remove or extinguish ignition or | Same |
| combustion sources. Evacuate |
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| or ventilate area. |
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Fire and explosion hazards | May decompose if contact with |
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| flames and heating elements. |
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| Container may explode if heated |
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| due to resulting pressure rise. |
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| Combustion products are toxic. |
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Storage conditions | Procedures/rules for CFC12 | Same |
| also apply for HFC134a |
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Disposal procedures | Recycle or reclaim | Same |
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Comparison of CFC12 and HFC134a Properties
Properties/Characteristics | CFC12 |
| HFC134a |
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Ozone Depletion Potential (ODP) | 1.0* |
| 0.0* |
Global Warming Potential (GPW) | 3.2* |
| 0.27* |
Molecular weight | 121 |
| 102 |
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Boiling point at 1 atmosphere | |||
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 |
HFC134a approximately 3 psig | |||
Pressure at 65°F (18°C) ambient | higher than CFC12 | ||
HFC134a approximately 2 psig | |||
Pressure at 65°F (18°C) ambient | lower than CFC12 |
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* Compared to CFC 11 = 1 |
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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 | 13 | RS1200001 |