Patent ID: 8239168
Filing Date: 2012-08-07
Classification: F24D,F24F,G05B

Abstract:
1. A system for detecting faults in an environmental control system for a building zone, the environmental control system controlled by a finite state machine that causes states of the environmental control system to change based on a varying climate condition, the system comprising: a circuit configured to receive a current value for the climate condition when the environmental control system is in a heating state and, during the heating state, to calculate an estimate of the climate condition at which a transition from the heating state to a state of no heating by the environmental control system is expected to be caused by the finite state machine; wherein the circuit is configured to determine, prior to beginning the transition from the heating state to the state of no heating, that a fault exists based on a comparison of: (a) the current value for the climate condition in the heating state, and (b) the estimate of the climate condition at which a transition from the heating state to the no heating state is expected to be caused by the finite state machine.