SOOT CLOGGING DETECTION METHOD FOR COMBUSTION DEVICE AND CO SENSOR TROUBLE DETECTION METHOD FOR CO SENSOR EQUIPPED COMBUSTION DEVICE BASED ON THE METHOD

摘要

PURPOSE: To make it possible to detect soot clogging in automatic mode by monitoring arithmetic operations of thermal efficiency one after another based on temperature information of a heating medium on the input and output of a heat exchanger and a flow rate of a heating medium and the supply of fuel and determining that a combustion device is clogged with soot, if the computed value drops to a specified value or blow. ;CONSTITUTION: When operating hot water supply heater or the like, thermal efficiency during combustion operation of a burner 1 is determined from the following equation: Thermal efficiency=effective amount of heat/amount of supplied heat-λ× (outside temperature-input temperature) × flow rate/(α× fuel supply) based on information about input temperature, output temperature, supply and flow rate of fuel in terms of a thermal efficiency arithmetic operation unit 24 where λ stands for a specific heat a heating medium, while α stands for amount of heat per unit volume. Then, a stabilization determinant unit 25 compares a preceding thermal efficiency with the latest thermal efficiency and when this difference between both values is small than an allowable range when the thermal efficiency is stabilized), an average thermal efficiency is determined by an average thermal efficiency computation unit 27. When this average thermal efficiency exceeds an allowable deviation value and drops below that, it is determined that the heat exchanger 2 is clogged with soot so that an annunciation unit 29 is operated.;COPYRIGHT: (C)1995,JPO