<p>Disclosed is a freezing unit provided with a first control unit (53) that adjusts the cooling performance of an evaporator (14) so that the internal temperature is at a target temperature, a second control unit (54) that increases the cooling performance of the evaporator (14) to lower the internal temperature to a second lower temperature limit, and then stops a compressor (11) and also opens an automatic ventilation opening (7) to introduce outside air into the unit once the temperature is maintained at the target temperature, and a third control unit (55) that causes control operation by the first control unit (53) to resume when the internal temperature subsequently reaches an upper temperature limit.</p>
