Heating and Air Conditioning: Service Precautions
INSTRUCTIONSWHEN HANDLING REFRIGERANT
1. R-134a liquid refrigerant is highly volatile. A drop on the skin of your hand could result in localized frostbite. When handling the refrigerant, be sure to wear gloves.
2. If the refrigerant splashes into your eyes, wash them with clean water immediately. It is standard practice to wear goggles or protective glasses to protect your eyes, and gloves to protect your hands.
3. The R-134a container is highly pressurized. Never leave it in a hot place, and check that the storage temperature is below 52 °C (126 °F).
4. A leak detector is often used to check the system for refrigerant leakage. Bear in mind that the R-134a, upon coming into contact with flame (this detector burns propane to produce a small flame), produces phosgene, which is a toxic gas.
5. Use only the recommended lubricant for R-134a A/C systems and components. If lubricants other than the recommended are used, system failure may occur.
6. The PAG lubricant absorbs moisture from the atmosphere at a rapid rate, therefore the following precautions must be observed:
- When removing refrigerant components from a vehicle, immediately cap the components to prevent moisture from entering the A/C system.
- When installing refrigerant components to a vehicle, do not remove the cap until just before connecting the components.
- Complete the connection of all refrigerant tubes and hoses without delay to prevent moisture from entering the A/C system.
- Use the recommended lubricant from a sealed container only.
7. If an accidental discharge in the system occurs, ventilate the work area before resuming service.
WHEN REPLACING A/C SYSTEM PARTS
1. Never open or loosen a connection before discharging the system.
2. Seal open fittings with a cap or plug immediately to prevent intrusion of moisture or dust.
3. Do not remove the sealing caps from a replacement component until it is ready to be installed.
4. Before connecting an open fitting, always install a new sealing ring. Coat the fitting and seal with refrigerant oil before making the connection.
WHEN INSTALLING CONNECTING PARTS
FLANGE WITH GUIDE PIN
Check the new O-ring for damage or if missing (use only specified O-rings) and lubricate using compressor oil. Tighten the nut by hand while pushing the pipe. Tighten the nut to the specified torque.
HANDLING TUBING AND FITTINGS
The internal parts of the refrigeration system will remain in a state of chemical stability as long as pure moisture-free refrigerant and refrigerant oil are used. Abnormal amounts of dirt, moisture or air can upset the chemical stability and cause problems or serious damage.
THE FOLLOWING PRECAUTIONS MUST BE OBSERVED
1. When it is necessary to open the refrigeration system, have everything you will need to service the system ready so that the system will not be left open any longer than necessary.
2. Cap or plug all lines and fittings as soon as they are opened to prevent the entrance of dirt and moisture.
3. All lines and components in parts stock should be capped or sealed until they are ready to be used.
4. Never attempt to rebend formed lines. Use the correct line for the installation you are servicing.
5. All tools, including the refrigerant dispensing manifold, the gauge set manifold and test hoses should be kept clean and dry.