In a support server communicable with a computer through a network, a first receiving unit is configured to receive a control parameter and communication state data transmitted from a readerwriter, a determining unit is configured to determine an update control parameter based on the received control parameter and the communication state data. In an air conditioner including a refrigerant circuit configured by the interconnection of a heat source unit and utilization units via refrigerant communication pipes, a refrigerant quantity determining system determines the adequacy of the refrigerant quantity and includes a state quantity storing means and a refrigerant quantity determining means. The third web portion is provided with an inwardly extending return portion at an edge of the third web portion embedded in the foam insulation between the inner and outer skins.