Standing pilot furnace with vented vestibule

An induced draft, fuel-fired furnace, comprising:

• a heat exchanger having an inlet and an outlet;
• a vent including an inlet and a venturi section;
• a burner;
• a vented vestibule in fluid communication with said vent;
• a blower having an inlet in fluid communication with said heat exchanger outlet and an outlet in fluid communication with said vent inlet;
• and
• a standing pilot disposed in said furnace such that combustion products provided thereby are in fluid communication with said venturi section, said standing pilot adapted to ignite fuel operably discharged from said burner.

An induced draft, fuel-fired furnace, comprising:

• a heat exchanger having an inlet and an outlet;
• a vent having an inlet;
• means for providing an area of lower pressure, said providing means defined at least in part by said vent;
• a vented vestibule;
• a burner disposed within said vestibule and in fluid communication with said heat exchanger inlet and said area of lower pressure;
• an induced draft blower having an inlet disposed in fluid communication with said heat exchanger outlet and an outlet disposed in fluid communication with the inlet of said vent;
• and
• means for igniting fuel operably discharged from said burner.

An induced draft, fuel-fired furnace, comprising:

• a vent having an inlet;
• a vented vestibule disposed in fluid communication with said vent, said vestibule comprising a plurality of panels;
• a blower having an inlet in fluid communication with the heat exchanger outlet, and an outlet disposed at the inlet of said vent;
• a drafthood disposed in said vestibule, said drafthood forming a plenum in fluid communication with said vent and including an inlet, said drafthood in fluid communication with an aperture formed in one of said vented vestibule panels, said drafthood including an undersurface formed with an inlet, and a blocked vented detecting means adapted to detect a blocked exhaust gas flow condition in said vent;
• a burner disposed in said furnace and in fluid communication with said drafthood inlet;
• and
• means for igniting fuel operably discharged from said burner.