PURPOSE: To prevent a clogging of tar by a method wherein a set temperature of a ceramic heater is made higher than an operating temperature in a normal combustion and a raised temperature is controlled at such a value as enabling to burn the adhered tar in the gasification pipe.
CONSTITUTION: The temperature of a gasification unit is controlled by a ceramic heater 6, and in case of empty burning for cleaning, the constant of a gasification heater control circuit is switched over, and the usual temperature is raised to the value which can remove the interior-adhered tar, thereby the cleaning is performed by blowing away the tar through its gasification. Further, it is possible to get a cleaned gasification pipe without having any tar adherance and an empty burning of the pipe for about ten minutes after one hour of starting of combustion every time. Thus, the tar may be removed at the start of the operation and the tar clogging can be prevented.
KOBAYASHI TOSHIROU
NEMOTO FUJIO
