To maintain a constant pressure in the evaporator when the system is running, an AXV does what to the refrigerant flow when the evaporator pressure drops?

An AXV, or Automatic Expansion Valve, is designed to adjust the flow of refrigerant into the evaporator based on the pressure within the evaporator. When the evaporator pressure drops, indicating that the cooling demand is increasing or that there is a drop in heat absorption, the AXV responds by increasing the flow of refrigerant. This adjustment is necessary to ensure that enough refrigerant enters the evaporator to absorb the heat from the space being cooled, thereby helping to maintain a constant pressure.

By allowing more refrigerant flow in response to a pressure drop, the AXV helps stabilize the system and prevent issues such as low pressure that can lead to inefficient cooling or system damage. This automatic adjustment is crucial for the effective operation of HVAC systems, as it ensures that they can adapt to varying load conditions without manual intervention. Therefore, the correct answer reflects the functioning of the AXV in maintaining consistent pressure within the evaporator.