Mazda CT-L1005, Training Manual

Page: 16 / 66

Fundamentals Basic Climate Control
Refrigerant
•
The refrigerant used in current Mazda vehicles is called R134a. It is a hydrofluorocarbon
(C
2
H
2
F
4
) that at normal atmospheric pressure boils at –26°C. This property, combined
with the fact that it does not harm the ozone layer, makes it an almost perfect substance
for A/C. However, R134a does still contribute to the greenhouse effect.
NOTE: Older Mazda vehicles use R12 refrigerant, which must not be used anymore. In
addition, R12 and R134a must not be mixed.
Pressure-Temperature Relationship of R134a
•
This chart shows the relationship between pressure and temperature for the refrigerant.
At normal atmospheric pressure of 1 bar, refrigerant will boil at –26°C. Above this curve
(area 1 in the diagram) the refrigerant is gaseous, below the curve (area 2 in the
diagram) it is liquid.
L1005_023
X Pressure Y Temperature
1 Gaseous refrigerant (above the curve) 2 Liquid refrigerant (below the curve)
02-10 Curriculum Training