1. A supervisory controller for a heating, ventilation, and air conditioning (HVAC) system, comprising: a data management module configured to receive a zone demand signal from a local controller of a zone of the HVAC system and receive a number of additional signals from a number of sensors, wherein the zone demand signal corresponds to an energy demand amount of the zone and the number of sensors include a gas consumption sensor configured to sense an amount of energy consumed by the HVAC system; a parameter identification module configured to determine, based on the zone demand signal, whether the zone is in a comfort state; an optimization module configured to: adjust an amount of energy supplied to the zone based on the amount of energy consumed by the HVAC system sensed by the gas consumption sensor; increase the amount of energy supplied to the zone if the zone demand signal is 100% by increasing a hot water temperature set point for water provided to the zone; and decrease the amount of energy supplied to the zone if the zone demand signal is less than 100% by decreasing the hot water temperature set point for water provided to the zone; and a model structure tuning module configured to, after the amount of energy supplied to the zone is increased or decreased by the optimization module: evaluate a model used to determine the amount of energy supplied to the zone; and; tune the model based on a heating plant of the HVAC system becoming disabled as a result of the heating plant not being functional.