System and control method for detecting an abnormal burning situation using air pressure sensing and flame detection
Disclosed is a method for detecting a combustion state of a boiler, and more particularly to a boiler and a method capable of exactly detecting an abnormal combustion state of a gas boiler using an air pressure sensor and a flame detection unit, thereby improving efficiency of the boiler. The method comprises the steps of (S1) supplying air to a burner through a fan, (S2) detecting whether an optimum amount of air is supplied through step (S1) by using the air pressure sensor, (S3) continuously detecting a status of a flame through the flame detection unit if the flame is made by an ignition part, (S4) converting a size of the flame into a corresponding voltage value, inputting the voltage value into a microcomputer, and comparing the voltage value with a preset target voltage value, (S5) stopping a combustion process if the microcomputer determines that the air pressure sensor erroneously operates based on a fact that a difference value between the voltage value and the preset target voltage value exceeds a reference value, and (S6) displaying an error message indicating an abnormal combustion state if the microcomputer determines that the air pressure sensor erroneously operates.
1. A method of controlling a boiler, which detects an abnormal combustion state using an air pressure sensor and a flame detection unit, the method comprising the steps of:
(S1) supplying air to a burner through a fan;
(S2) detecting whether an optimum amount of air is supplied through step (S1) by using the air pressure sensor;
(S3) continuously detecting a status of a flame through the flame detection unit if the flame is made by an ignition part;
(S4) converting a size of the flame into corresponding voltage value, inputting the voltage value into a microcomputer, and comparing the voltage value with a preset target voltage value;
(S5) stopping a combustion process if the microcomputer determines that the air pressure sensor erroneously operates based on a fact that a difference value between the voltage value and the preset target voltage value exceeds a reference value; and
(S6) displaying an error message indicating an abnormal combustion state if the microcomputer determines that the air pressure sensor erroneously operates.
2. The method as claimed in claim 1 , wherein step (S3) comprises the steps of:
(S3a) selecting a frame rod scheme in which the flame detection unit directly makes contact with the flame;
(S3b) selecting an infrared sensor scheme in which the flame detection unit detects the flame based on a calorie of the flame;
(S3c) selectively employing any one of the frame rod scheme and the infrared scheme or both the frame rod scheme and the infrared scheme and setting the selected scheme in a program.
3. The method as claimed in claim 2 , wherein further comprising a step of preparing predetermined values corresponding to a calorie of the flame (kcal), current (mA), voltage (V), and combustion stopping due to excessive air or insufficient air in the form of a table and setting the table in the microcomputer.
4. The method as claimed in claim 1 , wherein step (S5) comprises the steps of:
(S5a) determining whether or not a signal detected by the flame detection unit corresponds to an allowable error range of the target voltage value according to a calorie, which is set by a user;
(S5b) determining that the flame detection unit normally operates if the detected signal corresponds to the allowable error range; and
(S5c) continuously determining whether or not the detected signal corresponds to the allowable error range for a predetermined time if the detected signal deviates from the allowable error range in the step S5b, and stopping the combustion process if it is determined that the detected signal deviates from the target value even when the predetermined time lapses.