System and control method for detecting an abnormal burning situation using air pressure sensing and flame detection

A boiler for detecting an abnormal combustion state, the boiler comprising:

• a burner arranged in a predetermined closed space;
• a fan installed at one side of the burner so as to supply air required for combustion;
• an air pressure sensor positioned at a predetermined portion of the fan so as to detect an amount of the supplied air;
• an ignition part provided at a bottom of the burner so as to make flames;
• a flame detection unit provided in the burner so as to detect the flames;
• and
• a microcomputer for outputting a variety of control signals by receiving electrical signals from the air pressure sensor and the flame detection unit, in which the microcomputer is configured to first determine whether or not the air pressure sensor normally operates by comparing an electrical signal from the air pressure sensor with a first predetermined reference value stored in the microcomputer, thereafter an electrical signal from the flame detection unit presenting a present combustion state is compared with a second predetermined reference value stored in the microcomputer, wherein the reference values are a target value corresponding to calories of the flame, to thereby determine whether the combustion state is abnormal or not,
• wherein the flame detection unit includes an infrared sensor, which is provided at a side of the burner so as to detect the flames.