Combustion air proving apparatus with burner cut-off capability and method of performing the same

Abstract

A combustion air proving (CAP) system for a burner assembly having a burner for providing heated air to a location, a controller, and a back plate, where outside air is fed to the burner via a conduit. The CAP system is connected to an inlet of the system. An outlet of the system is connected to the burner via the back plate. A damper within the system is translatable between open and closed positions for allowing and blocking air flow, respectively. A sensor measures an air flow parameter of air flow to the burner. The sensor communicates with the controller, which shuts down the burner if the parameter measured by the sensor meets a predetermined threshold value. An assembly installer may test for proper sensor and controller functions by translating the damper to the closed position and blocking outside air flow.

Thus, having described the invention, what is claimed is: 
     
         1 . An apparatus for heating air provided to a location, comprising:
 an air heating system and a controller, said system providing heated air to said location, and said controller monitoring said system, and having the capability to shut the air heating system down;   an air supply conduit feeding outside air to said air heating system; and   a combustion air proving (CAP) system including a sensor in electrical communication with said controller, said sensor measuring a parameter correlating to, or representative of, air flow of said outside air to said system, and communicating said parameter to said controller, wherein said controller monitors said parameter and is responsive to a change in parameter, such that a predetermined threshold initiates a shutdown sequence of said system, said controller programmed to determine whether a predetermined threshold value has been met, said predetermined threshold value including a measurement of negative pressure, vacuum, air flow volume, and/or temperature within said air heating system.   
     
     
         2 . The apparatus of  claim 1  wherein the sensor is a pressure sensor and the parameter is representative of a pressure level, such that a predetermined pressure level threshold signaled by said pressure sensor initiates a shutdown sequence of said system. 
     
     
         3 . The apparatus of  claim 1  wherein said controller detects a predetermined pressure drop, a near-vacuum condition, or a decrease in combustion air volume, in said air heating system, indicating a lack of air flow to said air heating system. 
     
     
         4 . The apparatus of  claim 1  further including a damper interchangeable between an open position and a closed position, said open position allowing said outside air to flow through said air supply conduit to said air heating system, and said closed position preventing or impeding air from flowing through said air supply conduit to said air heating system. 
     
     
         5 . The apparatus of  claim 4  further including an air flow conduit or body attachable to said air supply conduit, said body includes an inlet and an outlet for the passage of said outside air flow, said damper disposed within said combustion air proving system body. 
     
     
         6 . The apparatus of  claim 1  wherein the sensor is an air volume sensor or air temperature sensor. 
     
     
         7 . The apparatus of  claim 1  wherein said heating system is a burner. 
     
     
         8 . The apparatus of  claim 1  including a flapper connected to an actuator via a pivot rod, said flapper rotatable to block an intake of said air heating system, said actuator adjusted such that a switch is engaged completing an electrical circuit when said sensor measures a decrease in combustion air volume at said intake of said air heating system; said combustion air volume for a particular firing rate of said air heating system being unrestricted as forces from said combustion air volume rotate said actuator via said flapper and pivot rod into engagement with said switch. 
     
     
         9 . The apparatus of  claim 8  wherein said flapper rotates closer to a closed position when said air supply conduit has blockage that reduces combustion air volume, thereby disengaging said actuator from said switch, and thus opening electrical contacts of said switch. 
     
     
         10 . A combustion air proving system for monitoring combustion air supplied to a burner, comprising:
 a body having an inlet and an outlet for the passage of air flow;   a sensor disposed on said combustion air proving system body between the inlet and the outlet, the sensor monitoring a parameter correlating to, or representative of, said air flow, wherein said sensor is an air pressure sensor or an air flow sensor, and said parameter is an air pressure level or an air flow level, respectively; and   a damper for affecting the air flow monitored by said sensor, and a biasing member for maintaining the damper in an open position.   
     
     
         11 . The combustion air proving system of  claim 10  wherein said damper actuation is responsive to a damper lever or damper switch or damper knob. 
     
     
         12 . The apparatus of  claim 10  including a flapper connected to an actuator via a pivot rod, said flapper rotatable to block an intake of said air heating system, said actuator adjusted such that a switch is engaged completing an electrical circuit when said sensor measures a decrease in combustion air volume at said intake of said air heating system; said combustion air volume for a particular firing rate of said air heating system being unrestricted as forces from said combustion air volume rotate said actuator via said flapper and pivot rod into engagement with said switch. 
     
     
         13 . A method of operating a heating system, comprising:
 providing a controller to said heating system, said system providing heat to a location, said controller monitoring said heating system and having the capability to shut the heating system down;
 said heating system including: 
 an air supply conduit feeding outside air to said air heating system; and 
 a combustion air proving (CAP) system including a sensor in electrical communication with said controller, said sensor measuring a parameter and communicating said parameter to said controller, wherein said controller monitors said parameter and is responsive to a change in parameter, such that a predetermined threshold value of said parameter initiates a shutdown sequence of said system; 
   firing said heating system;   measuring via said sensor said parameter responsive to an air flowing to the heating system;   sending a signal via the sensor responsive to said parameter measurement to said controller;   determining whether a predetermined threshold value is met; and   shutting down the heating system via the controller when a signal from the sensor is determined by the controller to have reached a predetermined threshold value.   
     
     
         14 . The method of  claim 13  including measuring said parameter within said air supply conduit. 
     
     
         15 . The method of  claim 13  further including testing for air flow and sensor operation by preventing or impeding air flow and monitoring said parameter during said testing for air flow and sensor operation. 
     
     
         16 . The method of  claim 13  further including:
 starting up the heating system via said controller after shutting down; 
 measuring said parameter; 
 determining whether said threshold value is still present; and 
 shutting down the heating system via the controller if said threshold value is still present. 
 
     
     
         17 . The method of  claim 13  wherein said controller is programmed to determine whether said predetermined threshold value has been met, said predetermined threshold value including a measurement of negative pressure, vacuum, air flow volume, and/or temperature within said air heating system.