The invention relates to a gas burner comprising: an injection holder (2) with a gas injector (2.1); a burner body (3) adapted to be arranged at the injection holder (2), the burner body (3) comprising an opening (3.1) for enabling a gas flow from said gas injector (2.1) and a primary air flow in an area above said burner body (3); a burner cap (4) adapted to be arranged at the top side of the burner body (3), the burner cap (4) comprising a bottom portion (4.1) and a circumferential surface portion (4.2) protruding downwardly from said bottom portion (4.1), wherein the circumferential surface portion (4.2) comprises a plurality of flame ports (4.3) and said burner body (3) and said burner cap (4) confine a chamber (5) for providing a combustion mixture of gas and primary air; wherein the burner body (3) comprises a bulge-shaped protrusion (3.5) forming a continuous ridge below the burner cap (4) at least in the area in which the flame ports (4.3) are provided, said bulge-shaped protrusion (3.5) reducing the distance between the burner cap (4) and the burner body (3) in the area of the flame ports (4.3).

The invention relates to a gas burner comprising: an injection holder (2) with a gas injector (2.1); a burner body (3) adapted to be arranged at the injection holder (2), the burner body (3) comprising an opening (3.1) for enabling a gas flow from said gas injector (2.1) and a primary air flow in an area above said burner body (3); a burner cap (4) adapted to be arranged at the top side of the burner body (3), the burner cap (4) comprising a bottom portion (4.1) and a circumferential surface portion (4.2) protruding downwardly from said bottom portion (4.1), wherein the circumferential surface portion (4.2) comprises a plurality of flame ports (4.3) and said burner body (3) and said burner cap (4) confine a chamber (5) for providing a combustion mixture of gas and primary air; wherein the burner body (3) comprises a bulge-shaped protrusion (3.5) forming a continuous ridge below the burner cap (4) at least in the area in which the flame ports (4.3) are provided, said bulge-shaped protrusion (3.5) reducing the distance between the burner cap (4) and the burner body (3) in the area of the flame ports (4.3).

A fresh-air intake according to aspects of the disclosure includes an outer cover having a pair of side panels disposed in a generally parallel spaced relationship, a top panel coupled to, and disposed generally perpendicular to, each panel of the pair of side panels, a bottom panel disposed generally parallel to the top panel, and a front panel coupled to, and disposed generally perpendicular to, each panel of the pair of side panels and the top panel, the front panel having a window formed therein, a supply line coupled to the bottom panel, a weir extending above the bottom panel and surrounding a junction with the supply line, a baffle disposed inside the outer cover, the baffle being disposed inwardly of the window so as to prevent infiltration of moisture into the supply line, and a weep hole formed in the bottom panel.

A fresh-air intake according to aspects of the disclosure includes an outer cover having a pair of side panels disposed in a generally parallel spaced relationship, a top panel coupled to, and disposed generally perpendicular to, each panel of the pair of side panels, a bottom panel disposed generally parallel to the top panel, and a front panel coupled to, and disposed generally perpendicular to, each panel of the pair of side panels and the top panel, the front panel having a window formed therein, a supply line coupled to the bottom panel, a weir extending above the bottom panel and surrounding a junction with the supply line, a baffle disposed inside the outer cover, the baffle being disposed inwardly of the window so as to prevent infiltration of moisture into the supply line, and a weep hole formed in the bottom panel.

Provided is a water heater including a burner that receives a supply of combustion air from a fan, a heat exchanger having a heat transfer tube, and a combustion chamber case in which a combustion chamber of the burner is formed in the interior thereof and which is to be capable of guiding combustion gas generated by the burner to the heat exchanger. The water heater further includes a unit case that surrounds the combustion chamber case, and a region on the outside of the combustion chamber case within the unit case serves as an air pressure chamber having a higher pressure than the combustion chamber. Thus, combustion gas leakage to the outside can be prevented or suppressed appropriately by means of a simple configuration.

Provided is a water heater including a burner that receives a supply of combustion air from a fan, a heat exchanger having a heat transfer tube, and a combustion chamber case in which a combustion chamber of the burner is formed in the interior thereof and which is to be capable of guiding combustion gas generated by the burner to the heat exchanger. The water heater further includes a unit case that surrounds the combustion chamber case, and a region on the outside of the combustion chamber case within the unit case serves as an air pressure chamber having a higher pressure than the combustion chamber. Thus, combustion gas leakage to the outside can be prevented or suppressed appropriately by means of a simple configuration.

A gas burner for cooking appliances, having overlapping main flame and simmering flame rings, includes an injector holder assembly associated with a first and a second injector and positioned below a cooktop opening; and a head assembly associated at the top with the injector holder assembly and positioned above the cooktop opening, the head assembly having a first chamber communicating with the first injector and with doors for ejecting the gas and primary air mixture supplied to the main flame ring, and a second chamber communicating with the second injector and with a passageway for ejecting the gas and primary air mixture supplied to the simmering flame ring. The second chamber communicates with a through opening in the outer side walls of the head assembly to receive primary air from above the cooktop, and the head assembly completely seals the cooktop opening where the gas burner is to be installed.

A gas burner for cooking appliances, having overlapping main flame and simmering flame rings, includes an injector holder assembly associated with a first and a second injector and positioned below a cooktop opening; and a head assembly associated at the top with the injector holder assembly and positioned above the cooktop opening, the head assembly having a first chamber communicating with the first injector and with doors for ejecting the gas and primary air mixture supplied to the main flame ring, and a second chamber communicating with the second injector and with a passageway for ejecting the gas and primary air mixture supplied to the simmering flame ring. The second chamber communicates with a through opening in the outer side walls of the head assembly to receive primary air from above the cooktop, and the head assembly completely seals the cooktop opening where the gas burner is to be installed.

A promotion member is disposed a predetermined distance apart from an impregnation member disposed at an upstream side end of a combustion chamber, and an ignition device and a first air supply opening are prepared on an upstream side from the promotion member in an ignition space, and a second air supply opening is prepared on a downstream side from the promotion member in the ignition space. Fuel is supplied to a smooth surface of the impregnation member, and a concave part or cutout is formed in the impregnation member to house at least a part of the ignition device. A flow rate of air supplied to the combustion space through the second air supply opening becomes larger toward the downstream side. Thereby, ignitability in an evaporation type burner is improved and incomplete combustion of fuel on the downstream side of the combustion chamber is reduced.

A promotion member is disposed a predetermined distance apart from an impregnation member disposed at an upstream side end of a combustion chamber, and an ignition device and a first air supply opening are prepared on an upstream side from the promotion member in an ignition space, and a second air supply opening is prepared on a downstream side from the promotion member in the ignition space. Fuel is supplied to a smooth surface of the impregnation member, and a concave part or cutout is formed in the impregnation member to house at least a part of the ignition device. A flow rate of air supplied to the combustion space through the second air supply opening becomes larger toward the downstream side. Thereby, ignitability in an evaporation type burner is improved and incomplete combustion of fuel on the downstream side of the combustion chamber is reduced.