Audi Q5: Refrigerant Oil
General Information
Caution
When handling refrigerant oil, pay attention to
local regulations.
Refrigerant oil mixes with the refrigerant (about 20-40%,
depending on compressor type and amount of refrigerant) and
circulates constantly in the system, lubricating the moving
parts.
Special synthetic refrigerant oils, for example polyalkylene
glycol (PAG) oil, are used in conjunction with R134a air
conditioning systems. This is necessary as mineral oil, for
example, does not mix with R134a. In addition, the materials of
the R134a air conditioning system could be corroded as a result
of mixture flowing through the refrigerant circuit under
pressure at high temperatures or breakdown of the lubricating
film in the compressor. Using non-approved oils can cause the
HVAC system to malfunction. Only use approved oils.
Refer to the Parts Catalog.
Type of oil for R134a in motor vehicles: PAG. (Polyalkyleneglycol)
Note
- Do not store open containers of refrigerant oil because it
attracts moisture.
- Always keep oil containers sealed.
- Do not use old refrigerant oil over again. For disposing
refrigerant oil of unknown origin pay attention to local
regulations.
- Ester-based oils are only intended for use in large systems
at this time, not in passenger vehicle systems.
Refrigerant Oil Characteristics
The most important properties are a high degree of
solubility with refrigerant, good lubricity, absence of acid and
minimal water content. Only certain oils are permitted. For a
list of approved refrigerant oils and capacities. Refer to
→ Chapter "Approved Refrigerant Oils and Capacities".
PAG oils, which are appropriate for refrigerant R134a, are
highly hygroscopic and do not mix with other oils. Opened
containers should therefore be closed again immediately to
prevent ingress of moisture. Moisture and acids promote aging of
refrigerant oil, causing it to become dark and viscous as well
as corrosive towards metals.
Note
- Refrigerant oil, because of its chemical properties, must
not be disposed of with engine oils or transmission oils. For
disposing refrigerant oil of unknown origin pay attention to
local regulations.
- Only the oil approved for the A/C compressor may be used in
refrigerant circuits with refrigerant R134a. For the correct
oil. Refer to the Parts Catalog. For the correct capacities.
Refer to
→ Chapter "Approved Refrigerant Oils and Capacities".
READ NEXT:
General Information
The temperature in the passenger compartment depends on the
amount of heat radiated through the windows and conducted by the
metal parts of the body. In hot weather it is possibl
As per VBG 20, German industrial liability insurance
association.
Pay attention to the workshop-specific instructions. It
should be kept in the workshop.
Product Characteristics
Refrigerants use
Vehicles with a high-voltage system (hybrid vehicles)
Extremely Dangerous Due to High-Voltage
The high-voltage system is under high-voltage. Electrocution can
cause death or very serious personal inj
SEE MORE:
Information on Releasing and Disassembling Connector Housings
Note
Observe general notes for repairs on the vehicle electrical
system. Refer to
→ Chapter "Vehicle Electrical System, General Repair
Information".
Always use the release tools intended for the releasing
process. Un
Note
Switch pressures, removing and installing switches as well
as switch arrangement and version. Refer to vehicle specific
refrigerant circuit
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; System
Overview - Refrigerant Circuit (vehicle-specific
repair manua