A building control system that includes a central coordinator and one or more discrete air conditioner controllers configured to communicate with one or more discrete air conditioner units. The discrete air conditioner controller may include a wireless I/O block for receiving signals in a first signal format from the central coordinator and for transmitting signals to the one or more discrete air conditioner units in a second signal format. In some instances, the discrete air conditioner controller may be configured to wirelessly transmit a signal to at least one discrete air conditioner unit in response to receiving a signal from the central coordinator. This configuration may provide a measure of distributed control of the building control system in a cost effective and efficient manner.