Systems and methods for fault detection of air handling units
AssigneeJohnson Controls Technology Company
InventorsJohn M. House, John E. Seem
Life of this patent
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Abstract
A system is disclosed for detecting faults in an environmental control system for a building zone. The system includes a circuit configured to determine that a fault exists based on a comparison of the current value for the climate condition in a heating state and the estimate of the climate condition at which a transmission from the heating state to the no heating state is expected to be caused by a finite state machine of the system.
Claims20
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.
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 no heating state and, when in the no heating state, to calculate an estimate of the climate condition at which a transition from the no heating state to a heating state is expected to be caused by the finite state machine;
- wherein the circuit is configured to determine, prior to beginning the transition from the no heating state to the heating state, that a fault exists based on a comparison of:
- (a) the current value for the climate condition in the no heating state, and
- (b) the estimate of the climate condition at which a transition from the no heating state to the heating state is expected to be caused by the finite state machine.
A method for detecting faults in an environmental control system affecting a building zone, the method comprising:
- controlling the environmental control system using a controller implementing the control via finite state machine logic, the controller causing the environmental control system to change states based on a varying climate condition;
- receiving, at a circuit, a current value for the climate condition when the environmental control system is in a no heating state;
- calculating, using the circuit and during the no heating state, an estimate of the climate condition at which a transition from the no heating state to a heating state is expected to be caused by the controller's finite state machine logic;
- prior to beginning a transition from the no heating state to the heating state, comparing the current value for the climate condition when the environmental control system is in a no heating state to the estimate of the climate condition at which the transition from the no heating state to the heating state is expected to be caused;
- and
- determining that a fault exists based on the comparison.
A method for detecting faults in an environmental control system affecting a building zone, the method comprising:
- controlling the environmental control system using a controller implementing the control via finite state machine logic, the controller causing the environmental control system to change states based on a varying climate condition;
- receiving, at a circuit, a current value for the climate condition when the environmental control system is in a heating state;
- calculating, using the circuit and during the heating state, an estimate of the climate condition at which a transition from the heating state to a no heating state is expected to be caused by the controller's finite state machine logic;
- prior to beginning a transition from the heating state to the no heating state, comparing the current value for the climate condition when the environmental control system is in a heating state to the estimate of the climate condition at which the transition from the heating state to the no heating state is expected to be caused;
- and
- determining that a fault exists based on the comparison.
Dependencies are inferred from the claim text.