APPARATUS AND METHOD FOR LOGGING DATA FROM A HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM

A method for logging data from an HVAC system comprises the steps of: collecting, within a thermostat, a plurality of data elements corresponding to a current time, at least one user setting, at least one HVAC system state, and at least one environmental measurement; correlating, within the thermostat, the collected data elements according to the current time; and storing, within the thermostat, the collected data elements. The method may further comprise the steps of: transmitting the stored data elements from the thermostat to an external device; and analyzing, within the external device, the transmitted data to determine energy savings. The data may be transmitted from the thermostat when the thermostat receives a request from the external device. The data may be transmitted from the thermostat to the external device over a communication link comprising one of a hard-wired communication link or a radio frequency communication link.