Volkswagen Golf 1999 Service Manual page 3912

A/C refrigerant system, servicing
http://ebahn.bentleypublishers.com/vw/servlet/Display?action=Next&type=repair&id=...
Note:
The temperature/pressure relationship only
holds true when the refrigerant system
contains liquid and vapor, but not when it
contains only gas. In the gaseous state, the
temperature is approx. 10-30 C (18-54 F)
higher than indicated on the pressure gauge.
Measuring pressure and temperature in a
closed container or "switched-off"
refrigerant system
Due to the constant temperature/pressure
relationship of R-12 and R-134a,
approximate temperaturein a closed
container or in a switched-off A/C system
can be determined based on its pressure.
If the temperature displayed on a gauge is
lower than the actual temperature of the
refrigerant, the refrigerant container or
system is empty (discharged).
Note:
The temperature/pressure relationship only
holds true when the refrigerant system
contains liquid and vapor, but not when it
contains only gas. In the gaseous state, the
temperature is approx. 10-30 C (18-54 F)
higher than indicated on the pressure gauge.
Página 43 de 51
87-122
13/2/2005