# US 9,518,763 B2 · Performing integrity checks on climate control system components > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,518,763 B2 - Document ID: US9518763B2 - Status: Granted - Kind: B2 - Application number: 13/687,346 - Filed: 2012-11-28 - Published: 2014-05-15 - Granted: 2016-12-13 - Earliest claimed: 2012-11-09 - Assignees: Emerson Electric Co. - Applicants: Emerson Electric Co. - Inventors: John F. Broker; John J. Heller - Web page: https://patentgrep.com/patent/US9518763B2 ## CPC - F24H 9/2064: {for air heaters} - F24H 15/104: Inspection; Diagnosis; Trial operation - F24H 15/124: Preventing or detecting electric faults, e.g. electric leakage - F24H 15/20: characterised by control inputs - F24H 15/407: using electrical switching, e.g. TRIAC - F24F 11/32: Responding to malfunctions or emergencies - F24H 15/254: Room temperature - F24H 15/345: Control of fans, e.g. on-off control (control of fans of heat pump units F24H15/375) - F24H 15/36: of burners - F24H: FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL (steam generation F22) - F24F: AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING (removing dirt or fumes from areas where they are produced B08B15/00; vertical ducts for carrying away waste gases from buildings E04F17/02; tops for chimneys or ventilating shafts, terminals for flues F23L17/02) ## Abstract Exemplary embodiments are disclosed of a climate control system that includes an igniter and a controller having an igniter relay. The controller senses a current level through the igniter and senses voltage between terminals of a second relay of the controller. In a given one of a plurality of operational phases of the system, the controller is configured to compare the sensed current level and sensed voltage to a current level and voltage associated with a specific condition of the igniter, igniter relay, or second relay in the given phase. Based on a result of the comparing, the controller is configured to distinguish between a failure of one of the relays and a failure of the igniter. ## Claims ### Claim 1 A method performed by a controller of a climate control system having an igniter and an igniter relay, the method comprising: in one or more of a plurality of heating operational phases of the system, sensing current draw by the igniter and sensing voltage between terminals of a second relay of the system, where the current draw is sensed by a current sensing circuit connected across the igniter, the current draw sensing being performed independently of the igniter relay; for a given one of the heating operational phases in which the sensing is performed, comparing the sensed current and voltage with a current value and voltage value predetermined together for the igniter and second relay in relation to the given operational phase to indicate the presence of a condition specifically of the igniter, of the second relay, or of the igniter relay, the comparing performed using a processor; and based on the comparing, distinguishing between a failure of one of the relays and a failure of the igniter. ### Claim 2 (depends on 1) The method of claim 1, wherein the specific condition includes a failure of or a normal operating condition of the igniter, second relay, or igniter relay. ### Claim 3 (depends on 1) The method of claim 1, wherein the operational phases of the system include phases of an ignition sequence. ### Claim 4 (depends on 1) The method of claim 1, wherein the second relay is a humidifier relay. ### Claim 5 (depends on 4) The method of claim 4, further comprising detecting an open igniter relay, a welded igniter relay, or an igniter in normal operating condition in a phase in which the humidifier relay and the igniter are switched on. ### Claim 6 (depends on 1) The method of claim 1, performed by a furnace system controller. ### Claim 7 (depends on 4) The method of claim 4, comprising identifying one of a plurality of conditions including the humidifier relay is welded; the igniter relay is welded; the humidifier relay is open; the igniter relay is open; the igniter is open; and the igniter is in normal operating condition. ### Claim 8 (depends on 4) The method of claim 4, comprising detecting the humidifier relay as welded, the detecting performed in a heating operational phase in which the humidifier relay and the igniter are not switched on. ### Claim 9 (depends on 4) The method of claim 4, comprising detecting the igniter relay as welded or the humidifier relay as open, the detecting performed in a heating operational phase in which the humidifier relay is switched on and the igniter is not switched on. ### Claim 10 A furnace system comprising: an igniter; and a controller including an igniter relay, and a current sensing circuit connected across the igniter and configured to sense, independently of the igniter relay, a current level through the igniter, the controller configured to sense voltage between terminals of a second relay of the controller; the controller further configured to: in a given one of a plurality of operational phases of the system, compare the sensed current level through the igniter and sensed voltage across the second relay to a current level and voltage associated together with a specific condition of the igniter, igniter relay, or second relay in the given phase, the comparing performable using a processor of the controller; and based on a result of the comparing, distinguish between a failure of one of the relays and a failure of the igniter. ### Claim 11 (depends on 10) The furnace system of claim 10, further comprising a humidifier; and wherein the second relay includes a humidifier relay. ### Claim 12 (depends on 10) The furnace system of claim 10, wherein the specific condition is identified as one of the following: the second relay is identified as welded; the igniter relay is identified as welded; the second relay is identified as open; the igniter relay is identified as open; the igniter is identified as open; and the igniter is identified as in normal operating condition. ### Claim 13 (depends on 10) The furnace system of claim 10, wherein: the second relay includes a humidifier relay; and the controller is configured to detect the humidifier relay as welded in a phase in which the humidifier relay and igniter are not switched on. ### Claim 14 (depends on 10) The furnace system of claim 10, wherein the controller is configured to detect a welded igniter relay or an open humidifier relay in a phase in which the humidifier relay is switched on and the igniter is not switched on. ### Claim 15 (depends on 10) The furnace system of claim 10, wherein the controller is configured to detect an open igniter relay, a welded igniter relay, or an igniter in normal operating condition in a phase in which a humidifier relay and the igniter are switched on. ### Claim 16 (depends on 10) The furnace system of claim 10 comprised by a heating, ventilation and air conditioning (HVAC) system. ### Claim 17 (depends on 10) The furnace system of claim 10, wherein the operational phases of the system include phases of an ignition sequence. ### Claim 18 A controller for an HVAC or furnace system having a gas igniter and a humidifier, the controller comprising: an igniter relay for controlling the igniter, and a current sensing circuit connected across the igniter and configured to sense, independently of the igniter relay, a current level through the igniter; the controller configured to: sense voltage between terminals of a humidifier relay for controlling the humidifier; based on the sensing performed after a call for heat and prior to a pre-purge of the system, determine whether the humidifier relay is welded; based on the sensing performed after pre-purge begins and before igniter warm-up, determine whether the humidifier relay is open and determine whether the igniter relay is welded; and based on the sensing performed when the igniter is warming up and before a gas valve of the system is energized, determine whether the igniter is operating normally, determine whether the igniter is open, and determine whether the igniter relay is open. ### Claim 19 (depends on 18) The controller of claim 18, further configured to distinguish between a failure of a relay and a failure of the igniter.