When a zeotropic blend separates because one component evaporates faster than the others.
Fractionation happens when vapour is taken from a zeotropic blend, whether from the top of a cylinder or through a leak in the vapour space. The more volatile components leave first, so what remains no longer matches the designed composition and the system's pressures and capacity shift.
Prevent it by removing blends from the cylinder as liquid and metering that liquid into the system so it flashes before the compressor.
Exam work areas
B · Tools, piping and refrigerant handling