Performing integrity checks on climate control system components

• US 9,518,763 B2
• Filed: 11/28/2012
• Issued: 12/13/2016
• Est. Priority Date: 11/09/2012
• Status: Active Grant

• Current Assignee: Copeland Comfort Control LP (Emerson Electric Company)
• Original Assignee: Emerson Electric Company
• Inventors: Broker, John F., Heller, John J.
• Primary Examiner(s): Betsch, Regis
• Application Number:
  US13/687,346
• Publication Number:
  US 20140134548A1
• Time in Patent Office: 1,476 Days
• US Class Current: 1/1
• CPC Class Codes: F24F 11/32 Responding to malfunctions or emergencies
• CPC Class Codes: F24H 15/104 Inspection; Diagnosis; Trial operation
• CPC Class Codes: F24H 15/124 Preventing or detecting electric faults, e.g. electric leakage
• CPC Class Codes: F24H 15/20 characterised by control inputs
• CPC Class Codes: F24H 15/254 Room temperature
• CPC Class Codes: F24H 15/345 Control of fans, e.g. on-off control control of fans of heat pump units F24H15/375
• CPC Class Codes: F24H 15/36 of burners
• CPC Class Codes: F24H 15/407 using electrical switching, e.g. TRIAC
• CPC Class Codes: F24H 9/2064 for air heaters

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

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.

2. 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.

3. The method of claim 1, wherein the operational phases of the system include phases of an ignition sequence.

4. The method of claim 1, wherein the second relay is a humidifier relay.

5. 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.

6. The method of claim 1, performed by a furnace system controller.

7. 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.

8. 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.

9. 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.

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.

11. The furnace system of claim 10, further comprising a humidifier;

and wherein the second relay includes a humidifier relay.

12. 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.

13. 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.

14. 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.

15. 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.

16. The furnace system of claim 10 comprised by a heating, ventilation and air conditioning (HVAC) system.

17. The furnace system of claim 10, wherein the operational phases of the system include phases of an ignition sequence.

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.

19. The controller of claim 18, further configured to distinguish between a failure of a relay and a failure of the igniter.