The refrigerant flows through the coils on the back or under the freezer and through an expansion valve to the inside of the freezer. As the refrigerant passes through the expansion valve the pressure drops and hence the temperature also drops.
The noun MM has 1 sense: 1  1. a metric unit of length equal to one thousandth of a meter. 2  Meaning: 3  A metric unit of length equal to one thousandth of a meter. 4  Classified under: 5  Nouns denoting quantities and units of measure. 6  Synonyms: 7  millimeter; millimetre; mm. 8  Hypernyms (mm is a kind of...):
ddhhmmZMMMyy dd is the day of the month hh is the hour of a 24-hour day mm is the minute within the hour Z is the Greenwich Mean Time zone identifier (ZULU) MMM is the month of the year in alphabetic form yy is the two-digit year of the century.