Patent ID: 6099295
Filing Date: 2000-08-08
Classification: F23N

Abstract:
A fuel oil-type burner including:a fuel oil combustion chamber;a power source for providing an AC voltage;a hot surface ignitor electrode associated with said combustion chamber, said ignitor electrode being sintered to full density with essentially no porosity;a fan blower driven by a split-phase type of motor and having both a main and start winding for providing fuel oil and air to said combustion chamber;an AC/DC converter coupled to said AC voltage for providing a DC voltage output;a voltage regulator circuit to provide a regulated low voltage DC voltage output;a first controllable switch coupled between said AC voltage and said hot surface ignitor;a second controllable switch coupled between said AC voltage and said fan blower motor main winding;a third controllable switch coupled between said AC voltage and said fan blower motor auxiliary start winding;a flame detector associated with said combustion chamber for generating an electrical signal if a flame is detected; anda control assembly coupled to said series voltage regulator circuit, said flame detector, and said first, second, and third controllable switches for:energizing said first controllable switch to heat said hot surface ignitor with DC voltage from said AC voltage for a predetermined preheat time period;energizing said second and third controllable switches to operate said blower motor with said AC voltage during a predetermined trial ignition time period;de-energizing the third controllable switch immediately following said trial ignition time period to de-energize the start winding of said blower motor;causing said motor to continue to run during a time period of approximately one second, known as the ""flame test time period""; andturning the second controllable switch OFF to shut down the heater if no ignition occurs during said flame test time period.