It is vital to distinguish between the two pressure readings, especially when dealing with negative temperatures.
The is the pressure at which liquid R-12 and its vapor coexist in equilibrium at a given temperature. At -10°C, R-12 is typically in a low-temperature, low-pressure state common in evaporator coils.
It is important to note that R-12 is a CFC (Chlorofluorocarbon) and its production has been banned globally under the Montreal Protocol due to its ozone-depleting potential. Modern systems no longer use R-12.
