Abstract: There is provided a gas burner that comprises a surface. The surface forms a burner deck comprising burner deck portions and a separation surface. The burner deck portions have holes. The separation surface is arranged to separate the burner deck portions from each other. Less than 5.0% of a surface area of the burner deck is formed by a combined surface area of the holes. The burner deck portions are adapted to define reaction zones extending over the burner deck portions. The holes are adapted to provide gas to be combusted in the reaction zones. The burner deck portions are arranged relative to each other to prevent the reaction zones from extending over the separation surface.

Abstract: The invention pertains to a method for operating a surface stabilized fully premixed gas premix burner. The burner is adapted to modulate between a minimum load and a full load, the ratio of the full load over the minimum load being at least 4. The method comprises the step of supplying a premix of combustible gas and air to the burner at an air to combustible gas ratio, the combustible gas supplied to the burner comprises at least 20% by volume of hydrogen, In the method, the air to combustible gas ratio of the premix which is supplied to the burner when the burner is operated at minimum load is set by a mechanism to be in relative terms at least 20% higher than the air to combustible gas ratio of the premix which is supplied to the burner when the burner is operated at full load.

Abstract: There is provided a gas burner that comprises a surface. The surface forms a burner deck comprising burner deck portions and a separation surface. The burner deck portions have holes. The separation surface is arranged to separate the burner deck portions from each other. Less than 5.0% of a surface area of the burner deck is formed by a combined surface area of the holes. The burner deck portions are adapted to define reaction zones extending over the burner deck portions. The holes are adapted to provide gas to be combusted in the reaction zones. The burner deck portions are arranged relative to each other to prevent the reaction zones from extending over the separation surface.

Abstract: Method for starting a burner wherein a premixed gas comprising a combustible gas and air is supplied, wherein the combustible gas comprises at least 50% by volume of hydrogen. The method comprises the following steps: during a start-up phase: supplying premixed gas having a first lambda-value to the burner surface, wherein the first lambda-value is at least 1.85, and igniting the supplied premixed gas having the first lambda-value using an ignition source. During an operation phase after the premixed gas has been ignited: supplying premixed gas having a second lambda-value to the burner surface, wherein the first lambda-value is larger than the second lambda-value. Independent claims for a burner and a heating appliance are included.

Abstract: The invention pertains to a method for operating a surface stabilized fully premixed gas premix burner. The burner is adapted to modulate between a minimum load and a full load, the ratio of the full load over the minimum load being at least 4. The method comprises the step of supplying a premix of combustible gas and air to the burner at an air to combustible gas ratio, the combustible gas supplied to the burner comprises at least 20% by volume of hydrogen, In the method, the air to combustible gas ratio of the premix which is supplied to the burner when the burner is operated at minimum load is set by a mechanism to be in relative terms at least 20% higher than the air to combustible gas ratio of the premix which is supplied to the burner when the burner is operated at full load.

Abstract: A premix gas burner (100) comprises a metal mounting plate (102) for mounting the premix gas burner in a heating appliance; a metal plate structure (104) and a burner deck (106). The burner deck comprises a woven wire mesh on the outer surface of which premix gas is combusted after the premix gas has flown through the woven wire mesh. The woven wire mesh comprises a circumferential edge (108). The circumferential edge comprises a plurality of tabs (110). The mounting plate comprises a central opening. The burner deck is inserted through the central opening. The metal mounting plate or the metal plate structure comprises at least one ridge (112). The at least one ridge comprises at least one notch (114). Each of the tabs is positioned in a notch.

Abstract: A premix gas burner comprises a main body, a porous wall, a distribution chamber delimited by the main body and by the porous wall, and an entrance in the main body for introducing a premix of combustible gas and air into the distribution chamber. The main body comprises a cylindrical shape. The porous wall comprises a first porous wall segment and a second porous wall segment. The first porous wall segment and the second porous wall segment both comprise pores for the premix gas to flow from the distribution chamber through the pores, for combustion of the premix gas outside the distribution chamber. The first porous wall segment comprises or consists out of a shaped segment. The shaped segment is directed to the inside of the distribution chamber, such that when the burner is in use premix gas flows from the distribution chamber through the pores of the shaped segment to the inside of the shaped segment. The second porous wall segment comprises an annular porous wall segment.

Abstract: A premix gas burner comprises a metal plate structure, a burner deck and a shaped distributor plate. The metal plate structure is provided for mounting the premix gas burner in a heating appliance. The burner deck comprises a woven wire mesh on the outer surface of which premix gas is combusted after the premix gas has flown through the woven wire mesh. The shaped distributor plate comprises perforations. When the burner is in use the premix gas flows through the perforations of the shaped distributor plate before the premix gas flows through the woven wire mesh. One or more than one slot or notch shaped opening is provided in the shaped distributor plate. The woven wire mesh comprises a circumferential edge comprising at least one tab. The tab or tabs is/are inserted through a slot or notch shaped opening in the shaped distributor plate.

Abstract: A premix gas burner (100) comprises a metal mounting plate (102) for mounting the premix gas burner in a heating appliance; a metal plate structure (104) and a burner deck (106). The burner deck comprises a woven wire mesh on the outer surface of which premix gas is combusted after the premix gas has flown through the woven wire mesh. The woven wire mesh comprises a circumferential edge (108). The circumferential edge comprises a plurality of tabs (110). The mounting plate comprises a central opening. The burner deck is inserted through the central opening. The metal mounting plate or the metal plate structure comprises at least one ridge (112). The at least one ridge comprises at least one notch (114). Each of the tabs is positioned in a notch.

Abstract: A premix gas burner comprises a main body, a porous wall, a distribution chamber delimited by the main body and by the porous wall, and an entrance in the main body for introducing a premix of combustible gas and air into the distribution chamber. The main body comprises a cylindrical shape. The porous wall comprises a first porous wall segment and a second porous wall segment. The first porous wall segment and the second porous wall segment both comprise pores for the premix gas to flow from the distribution chamber through the pores, for combustion of the premix gas outside the distribution chamber. The first porous wall segment comprises or consists out of a shaped segment. The shaped segment is directed to the inside of the distribution chamber, such that when the burner is in use premix gas flows from the distribution chamber through the pores of the shaped segment to the inside of the shaped segment. The second porous wall segment comprises an annular porous wall segment.

Abstract: A cylindrical gas premix burner comprises a cylindrical burner deck onto which the flames are stabilized when the burner is in use; a mixing chamber inside the cylindrical burner deck; an inlet device mounted perpendicularly to the axial direction of the cylindrical burner deck for the supply of premix gas into the mixing chamber; and an end cap closing off the mixing chamber at the side opposite to the side where the inlet device is provided. The inlet device comprises a perforated metal plate. The perforations in the perforated metal plate are provided for the supply of premix gas into the mixing chamber. The perforated metal plate is dome shaped; such that perforations in the perforated metal plate are located at different height levels from the base of the cylindrical burner deck.

Abstract: A sectional heat exchanger for a condensing heat cell comprises two end segments and one or more than one intermediate segment(s). The one or the more than one intermediate segment(s) and the two end segments are assembled in the heat exchanger. A combustion chamber is provided in the sectional heat exchanger. Each of the one or the more than one intermediate segment(s) comprises at least one water flow channel for water to be heated. Between each two consecutive segments at least one flue gas flow channel is provided, extending from the combustion chamber. The one or the more than one intermediate segment(s) each comprise a horizontal row of ribs extending into the flue gas flow channel in order to increase heat exchange from the flue gas to the water to be heated. Ribs at the two outer sides of the horizontal row of ribs have a larger height than ribs in the middle of the row of ribs. With height of the rib is meant the dimension of the rib in the vertical direction of the sectional heat exchanger.

Abstract: A sectional heat exchanger for a heat cell. The sectional heat exchanger having two end segments and one or more intermediate segment(s) provided between the two end segments which are assembled in the heat exchanger. A combustion chamber is provided in the sectional heat exchanger, perpendicular to the one or more intermediate segment(s), each of the one or more intermediate segments having at least one flow channel for a fluid to be heated. In between each two consecutive segments at least one flow channel for flue gas is present. The total width of the sectional heat exchanger decreases over at least part of the length in the direction away from the combustion chamber. The depth of the flow channels for flue gas decreases in the direction away from the combustion chamber. The distance between the two walls delimiting the intermediate segment increases in the direction away from the combustion chamber.

Abstract: The heat exchanger comprises at least one gas flow channel, at least one water flow channel, and a metal wall delimiting the gas flow channel from the water flow channel. The at least one water flow channel comprises a number of consecutive parallel straight segments. Two consecutive parallel straight segments are separated by a wall and by a U-turn comprising an upstream section and a downstream section. The upstream and the downstream sections are defined as the sections of the U-turn delimited on the one hand by the plane of the wall separating the two consecutive parallel straight segments; and on the other hand by the plane through the end section of the wall separating the two consecutive parallel straight segments, the plane which is parallel with the width direction of the water flow channel and which is perpendicular to the plane of the wall separating the two consecutive parallel straight segments.

Abstract: The heat exchanger comprises at least one gas flow channel, at least one water flow channel, and a metal wall delimiting the gas flow channel from the water flow channel. The at least one water flow channel comprises a number of consecutive parallel straight segments. Two consecutive parallel straight segments are separated by a wall and by a U-turn comprising an upstream section and a downstream section. The upstream and the downstream sections are defined as the sections of the U-turn delimited on the one hand by the plane of the wall separating the two consecutive parallel straight segments; and on the other hand by the plane through the end section of the wall separating the two consecutive parallel straight segments, the plane which is parallel with the width direction of the water flow channel and which is perpendicular to the plane of the wall separating the two consecutive parallel straight segments.

Abstract: A premix gas burner comprises a burner deck which comprises a fiber based substrate and a perforated plate or a screen supporting the fiber based burner substrate. The premix gas burner further comprises at least two contact wires that are forming a thermocouple. The contact wires are directly or indirectly fixed to the burner deck to measure a temperature of the burner deck when the premix gas burner is in operation. The fiber based substrate is locally at least partly connected directly or indirectly to the perforated plate or the screen in the region where the contact wires of the thermocouple are directly or indirectly fixed to the burner deck.

Abstract: A sectional heat exchanger for a heat cell. The sectional heat exchanger having two end segments and one or more intermediate segment(s) provided between the two end segments which are assembled in the heat exchanger. A combustion chamber is provided in the sectional heat exchanger, perpendicular to the one or more intermediate segment(s), each of the one or more intermediate segments having at least one flow channel for a fluid to be heated. In between each two consecutive segments at least one flow channel for flue gas is present. The total width of the sectional heat exchanger decreases over at least part of the length in the direction away from the combustion chamber. The depth of the flow channels for flue gas decreases in the direction away from the combustion chamber.

Abstract: A gas premix burner including a perforated plate, a woven wire mesh or an expanded metal sheet; and a woven, knitted or braided burner deck having metal fibers supported by the perforated plate, woven wire mesh or expanded metal sheet. The woven, knitted or braided burner deck has at least a zone with a high density of at least 1250 g/dm3.

Abstract: The present invention provides a new heat exchanger element comprising a premix burner with an outward curved or ridged burner surface. The heat exchanger element further comprises a combustion chamber. The combustion chamber is bound on one side by the burner and is further made up of water cooled metal walls which, starting from the burner and in downstream direction, first widen and thereafter narrow down to the width of a customary heat exchanger element. This creates enough space for a proper combustion, avoiding dead angles and recirculation or too early ending of the combustion reaction, thereby reaching low emissions of NOx and CO.

Abstract: A premix gas burner comprises a burner deck which comprises a fiber based substrate and a perforated plate or a screen supporting the fiber based burner substrate. The premix gas burner further comprises at least two contact wires that are forming a thermocouple. The contact wires are directly or indirectly fixed to the burner deck to measure a temperature of the burner deck when the premix gas burner is in operation. The fiber based substrate is locally at least partly connected directly or indirectly to the perforated plate or the screen in the region where the contact wires of the thermocouple are directly or indirectly fixed to the burner deck.