Heating and Air Conditioning: Service Precautions

Safety Precautions

The subassemblies and lines of the air conditioner are filled with Tetrafluoroethane also known as refrigerant R-134a.

A label on the lock carrier in the engine compartment indicates the refrigerant type and capacity.

CAUTION!
• Always use an Underwriter's Laboratory (UL) approved refrigerant recovery/recycling/recharging unit such as Kent-Moore ACR4, or equivalent, whenever discharging an R-134a A/C system

• As of January, 1992 any person who services a motor vehicle air conditioner MUST, by law, be properly trained and certified and use approved refrigerant recycling equipment. Technicians must complete an EPA approved recycling course to be certified

• State and Provincial governments may have additional requirements regarding air conditioning servicing. Always comply with local laws

CAUTION!
A/C system is filled with refrigerant gas which is under pressure

Always be careful that refrigerant does not come in contact with your skin

If liquid refrigerant has come in contact with your skin or eyes:

• Do not rub skin or eyes

• Immediately flush with cool water for 15 minutes

• Rush to a doctor or hospital

• Do not attempt to treat yourself

Work in a well ventilated area because refrigerant gases are heavier than air, displace oxygen and may cause suffocation in areas of poor air circulation, like under the car

Avoid breathing refrigerant vapors. Exposure may irritate eyes, nose and throat

Always wear hand and eye protection (gloves and goggles) when working around the A/C system

Keep refrigerant containers stored below 50°C (122°F) and never drop from high places. DO NOT warm refrigerant containers with an open flame. If refrigerant needs to be warmed, place bottom of tank in warm water.

Keep refrigerant away from open flames because poisonous gas will be produced if it burns. Do not smoke when refrigerant gases are present for the same reason

CAUTION!
• Electric welding near refrigerant hoses causes R-134a to decompose from ultraviolet light. Discharge system before electric welding

• Pressurized R-134a refrigerant in the presence of oxygen may form a combustible mixture. Never introduce compressed air into any R-134a container (full or empty), A/C component or piece of service equipment

• Do not expose any component of the A/C system to high temperatures (for example, open flames). Excessive heat will cause a pressure increase which could burst the system

• Do not steam clean condensers or evaporators. Use only cold water or compressed air

CAUTION!
Before beginning repairs on the electrical system:

• Obtain the anti-theft radio security code.

• Switch off all electrical consumers.

• Switch off ignition and remove ignition key.

• Disconnect negative ( - ) battery terminal.

• When disconnecting and reconnecting battery terminals, observe all applicable Notes and torque specifications, as well as instructions on performing OBD program and electrical system function checks as specified.

• R-12 and R-134a refrigerant are NOT compatible. Never add R-12 refrigerant to an R-134a system or R-134a refrigerant to an R-12 system. If the refrigerants are mixed, total system contamination will occur and compressor failure may result

• Refrigerant oils used for the R-134a system and R-12 system are NOT compatible. Use only the specified synthetic oil (Polyalkylene Glycol/PAG) for the R-134a refrigerant system. DO NOT use R-12 system oil in an R-134a system or R-134a system oil in an R-12 system. If the refrigerant oils are mixed, system contamination will occur and compressor failure may result

CAUTION!
• R-134a refrigerant system oil (PAG oil) absorbs moisture very rapidly. Moisture combines with the refrigerant to form acids which will damage the system. Use only the specified oil from a sealed container and ALWAYS reseal oil container immediately after use. DO NOT use oil if it has become contaminated with moisture

• Immediately plug open connections on A/C components to prevent dirt and moisture contamination. Likewise, DO NOT remove new components from packaging until ready to install. Immediately tighten component connections after installation

• Always use separate refrigerant recovery/recycling/recharging servicing equipment for R-12 and R-134a systems. DO NOT use one piece of equipment for both R-12 and R-134a systems. The residual traces of refrigerant will contaminate and damage the equipment. Servicing equipment includes recovery/recycling/recharging unit, charging station, vacuum pump, manifold gauges, etc.

• DO NOT use R-12 servicing equipment on R-134a systems or R-134a equipment on R-12 systems or damage to both the vehicle A/C system and servicing equipment may result. Use only equipment designed to meet Society of Automotive Engineers (SAE) standards

CAUTION!
• R-134a and R-12 systems use different size service fittings. NEVER use adaptors to convert an R-12 fitting to R-134a size or R-134a fitting to R-12 size

• R-134a and R-12 A/C components including compressor, hoses, O-rings, evaporator, condenser, receiver-drier, etc. are NOT interchangeable. Components of the R-134a system are identified by lettering (R-134a) or by a green label (or stripe). In addition a label on the upper radiator support identifies which type refrigerant is used. Use only the correct system component for each refrigerant type

CAUTION!
• Always replace damaged and/or leaking A/C system components. Do not attempt repair by soldering or welding

• Work area must be extremely clean when working on A/C system components

• Discharge A/C system before removing any A/C system component

• Always reinstall caps over A/C service valves

• Always replace O-rings, DO NOT reuse. Use only the correct size and type of O-rings specified for use with R-134a refrigerant. Lubricate O-ring with refrigerant oil before installing