Refrigerator appliances having multiple fluidly-connected, chilled chambers

A refrigerator appliance comprising:

• a cabinet defining an evaporator chamber;
• a first liner attached to the cabinet and defining a first chilled chamber having a primary air inlet, a secondary air inlet, and an air outlet;
• a second liner attached to the cabinet and defining a second chilled chamber spaced apart from the first chilled chamber, the second chilled chamber having an air inlet and an air outlet;
• a first fan in fluid communication with the evaporator chamber and the first chilled chamber;
• a second fan in fluid communication with the evaporator chamber and the second chilled chamber;
• a return line extending in fluid communication from the air outlet of the second chilled chamber to the secondary air inlet of the first chilled chamber, the return line being unobstructed from the second chilled chamber to the first chilled chamber;
• and
• a controller in operative communication with the first fan and the second fan, the controller being configured to initiate a single-chamber cooling operation, the single-chamber cooling operation comprising
• activating the first fan to motivate a first-fan (FF) cooling airflow from the evaporator chamber to the first chilled chamber, and
• activating the second fan to generate a second-fan (SF) positive stagnation pressure from the evaporator chamber, through the second chilled chamber, and to the secondary air inlet of the first chilled chamber, the SF positive stagnation pressure preventing an airflow through the return line.