Patent KR-20000046672-A (KR)
Title: Method for controlling combustion in heating operation by using temperatures of discharging heating water and returning heating water in gas boiler
Inventor: KIM CHANG YEON
IPC: F24H9/20
Filed: 1998-12-31
Abstract: PURPOSE: A method for controlling combustion in heating operation by using temperatures of discharging heating water and returning heating water in gas boiler is provided to rapidly determine a heat quantity(Qd) required to combust for heating by using the temperatures(Tout, Tin) obtained from a thermistor 1 mounted in a line for discharging heating water and a thermistor 2 mounted in a line for returning heating water and a user's set temperature(Tset). Also, the method is provided to control the heating combustion by calculating a rotating speed(.phi.M) of an exhaust fan from the heat quantity(Qd) and calculating an electric current value(PmA) for regulating a gas proportion valve for controlling a quantity of combustion gas after detecting the rotating speed(.phi.M). CONSTITUTION: A method for controlling combustion in heating operation by using temperatures of discharging heating water and returning heating water in gas boiler comprises the following steps: a step for detecting a low water level, a short, thermistors(TH1, TH2), and a state of a remote controller; a step for detecting whether a user uses hot water or not; a step for receiving a user's set temperature(Tset), a temperature of discharging heating water(Tout), and a temperature of returning heating water(Tin) by a microcomputer; a step for detecting whether the user s set temperature(Tset) is within a temperature range used in normal heating operation or not; a step for performing forcible combustion for a predetermined time period(Asec) in response to a control to an open/close degree of the gas proportion valve set previously and input and simultaneously calculating overall heat quantity required in heating; a step for calculating a rotating frequency of an exhaust fan from the calculated overall heat quantity and operating the exhaust fan; a step for detecting an error state to determine operating condition of the exhaust fan; a step for calculating an electric current value for controlling the proportion valve; a step for maintaining a proportional combustion; a step for calculating a temperature difference(.delta.T) between the temperature of discharging heating water(Tout) and the temperature of returning heating water(Tin) and then performing a control to the equilibrium of the temperature difference; a step for extinguishing the combustion according to the conditions of the temperature difference(.delta.T), a temperature difference(.delta.T1) between the user's set temperature(Tset) and the temperature of discharging heating water(Tout), and a temperature difference(.delta.T2) between the user's set temperature(Tset) and the temperature of returning heating water(Tin); a step for igniting again and then starting to combust according to the conditions of the temperature difference(.delta.T), a temperature difference(.delta.T1) between the user's set temperature(Tset) and the temperature of discharging heating water(Tout), and a temperature difference(.delta.T2) between the user's set temperature(Tset) and the temperature of returning heating water(Tin); a step for subsequently repeating a step for counting the re-combustion and performing the forcible combustion for a time period set previously; and a step for stopping the control to the combustion, if the count value reaches to a predetermined times.