Biological sample analyzer with forced air convection plenum

A biological sample analyzer, comprising:

• a housing having at least one outer wall that defines an internal cavity therein, defines an air intake extending though the at least one outer wall, and defines an air exhaust extending through the at least one outer wall;
• a plenum disposed within the internal cavity and having at least one plenum wall that defines an air duct therein, the air duct being in fluid communication with the air intake and the air exhaust;
• a receptacle disposed within the internal cavity, wherein the receptacle is configured to support a consumable holder containing a biological sample, at least a portion of the receptacle being supported within the air duct such that at least one air gap is defined between the receptacle and the at least one plenum wall;
• at least one heater disposed with the plenum and configured to apply heat to the consumable holder so as to heat the consumable holder when the consumable holder is supported by the receptacle;
• and
• a fan configured to force air along a path that extends from the air intake, through the at least one air gap, and to the air exhaust so as to cool the at least one heater;
• wherein the at least one heater is configured to apply an elevated temperature to the receptacle, the elevated temperature being above a target temperature for the receptacle, and the fan is configured to force air over the at least one heater before the consumable holder exceeds the target temperature so as to cool the at least one heater to the target temperature.

A method of operating a biological sample analyzer, the method comprising steps of:

• inserting a consumable holder containing a biological sample into a receptacle supported in an internal cavity of a housing of the biological sample analyzer, at least a portion of the receptacle being disposed in a plenum that is disposed in the internal cavity;
• causing at least one heater supported by the receptacle in the plenum to apply heat to the receptacle so as to heat the consumable holder wherein the at least one heater is caused to apply heat at an elevated temperature and then at a target temperature below the elevated temperature;
• and
• causing a fan to force air along a path that extends from an air intake defined by the housing, through at least one air gap in the plenum defined between the receptacle and at least one plenum wall of the plenum, and to an air exhaust defined by the housing so as to cool the receptacle wherein the fan is caused to operate at a first speed when the heat is applied at the elevated temperature, and the fan is caused to operate at an increased speed that is faster than the first speed when the temperature of the at least one heater is decreasing from the elevated temperature to the target temperature.