1. An HVAC data processing and communication network, comprising: at least one environmental sensor and at least one subnet; and a subnet controller configured to: determine a number of said at least one environmental sensor, a number of said at least one subnet and a number of damper controllers within said communication network; and automatically set up said communication network for zoned operation only when said subnet controller determines that there are at least two of said at least one environmental sensor and either of at least two of said at least one subnet or at least one of said damper controllers within said communication network.