Method of and system for flame sensing and diagnostic
AssigneeLennox Industries Inc.
InventorMichael Engler
Life of this patent
Estimating the term…
Abstract
A method of determining presence of a flame in a furnace of a heating, ventilation, and air conditioning (HVAC) system. The method comprises determining, using a controller, whether a processor signal (G) is active, responsive to a determination that the processor signal (G) is active, determining, using the controller prior to assertion of a flame-test input control signal, an output state of a first comparator, responsive to a determination that the output state of the first comparator is high, determining, using the controller prior to assertion of the flame-test input control signal, an output state of a second comparator, and responsive to a determination that the output state of the second comparator is low, transmitting, using the controller, a notification that a flame is present.
Claims24
A method of determining presence of a flame in a furnace of a heating, ventilation, and air conditioning (HVAC) system, the method comprising:
- determining, using a controller, whether a processor signal (G) is active;
- responsive to a determination that the processor signal (G) is active, determining, using the controller prior to assertion of a flame-test input control signal, an output state of a first comparator;
- responsive to a determination that the output state of the first comparator is high, determining, using the controller prior to assertion of the flame-test input control signal, an output state of a second comparator;
- and
- responsive to a determination that the output state of the second comparator is low, transmitting, using the controller, a notification that a flame is present.
A heating, ventilation, and air conditioning (HVAC) system comprising:
- circuitry for determining presence of a flame, the circuitry comprising:
- a flame detect circuit;
- a tank circuit;
- a first comparator;
- a second comparator;
- and
- a controller operatively coupled to the flame detect circuit, the tank circuit, the first comparator, and the second comparator, wherein the controller is configured to:
- determine whether a processor signal (G) is active;
- responsive to a determination that the processor signal (G) is active, determine, prior to assertion of a flame-test input control signal, an output state of a first comparator;
- responsive to a determination that the output state of the first comparator is high, determine, prior to assertion of the flame-test input control signal, an output state of a second comparator;
- and
- responsive to a determination that the output state of the second comparator is low, transmit a notification that a flame is present.
Dependencies are inferred from the claim text.