Patent ID: 7104460
Filing Date: 2006-09-12
Classification: F23N,F24F,Y02B

Abstract:
1. A method of determining a concentration C of carbon dioxide (CO 2 ) in air discharged from a recirculating air heater having a burner, an outside air damper, and a recirculating air damper inversely interlocked with the outside air damper, said method comprising the steps of: adjusting the outside air damper to a plurality of outside air damper positions; sensing an amount of airflow flowing through the outside air damper at each of the plurality of outside air damper positions; recording the amount of airflow and an outside air damper position value at each of the plurality of outside air damper positions; interpolating a curve relating the amount of airflow to the outside air damper position for all possible outside air damper positions between a minimum damper position and a maximum damper position; determining an amount of airflow through the outside air damper of the heater based on a current outside air damper position and utilizing the curve relating the amount of airflow to the outside air damper position; calculating a proportion P of outside air brought through the burner based on the current outside air damper position; determining a temperature difference ΔT between a supply air temperature T receiving a factor K based on a type of fuel used in the heater; and determining the concentration C of CO