Refrigerant And Refrigerant Oil
Refrigerant
- Refrigerant systems may only be filled with the refrigerant that is specifically approved by the manufacturer for the vehicle.
- A/C Service Stations may only be used with the refrigerant they were designed for.
- An information label -A- indicating the refrigerant used is provided in the engine compartment on the lock carrier or in the plenum chamber.
- Different refrigerants are never to be mixed.
Refrigerant Oil
- Refrigerant oil mixes with the refrigerant (approximately 10-40% depending on the compressor type and refrigerant quantity). The continuous circulation in the refrigerant circuit lubricates the moving parts.
- Special synthetic refrigerant oils are used in connection to R1234yf-A/C systems, for example polyalkylene glycol-based (PAG) oil with specific additives adjusted for the refrigerant. This is necessary, because for example mineral oil does not mix with R1234yf and because without these additives unwanted reactions to the refrigerant or the refrigerant circuit components can occur. In addition, the components of the A/C system could be affected if the mixture flows through the refrigerant circuit under pressure at high temperatures or the lubricating film in the A/C compressor tears. The use of non-approved oils can lead to the failure of the A/C system and exclusive use is therefore to be made of authorized refrigerant oils. Refer to the appropriate Electronic Parts Information.
- The specifically developed refrigerant oils for the refrigerant circuit with refrigerant R1234yf and R134a may only be used in a refrigerant circuit if the required approvals for this are available. Refer to the appropriate Electronic Parts Information and REFRIGERANT OIL .
- The most important properties are the high degree of solubility with refrigerant, good lubrication, no acid content and very minimal water content. For this reason only very specific oils may be used. Refer to the appropriate Electronic Parts Information and the REFRIGERANT CAPACITIES for a list of the approved refrigerant oils and capacities.
- PAG oils, which are appropriate for refrigerant R1234yf, are highly hygroscopic and do not always mix with other oils. For this reason only use approved refrigerant oils.
- Moisture and acids promote aging of refrigerant oil, causing it to become dark and viscous as well as corrosive towards metals. For this reason, keep containers with refrigerant oil closed to protect it from moisture and close opened containers immediately.
- Only refrigerant oil that is approved for the respective refrigerant and the A/C compressor that is installed may be used. Refer to the appropriate Electronic Parts Information.
- Do not use ester-based oils (polyolester oils/POE oils). These are currently only for larger systems under different operating conditions (not for vehicle A/C systems).
- Do not leave containers of refrigerant oil open when storing because it is hygroscopic (it attracts moisture).
- Always keep containers with refrigerant oil and the refrigerant circuit closed.