A heat exchanger plate for a plate heat exchanger (12) includes a first side, a second side and a center point (P) through which an imaginary center axis (A) extends in a direction perpendicular to a plane of the plate. The plate comprises a first port for a first medium, and at least a second port and a third port for a second medium. The plate further comprises a first sealing arranged on the second side around the first port, a second sealing arranged on the second side at a circumference of the plate, and a closed third sealing arranged between the first and second sealings to form a first heat transfer area and a second heat transfer area separated from the first heat transfer area. The second port is arranged in the first heat transfer area and the third port is arranged in the second heat transfer area.

A heat exchanger comprising a mixture inflow unit into which a mixture of air and fuel is introduced, a burner for combusting the mixture introduced through the mixture inflow unit, a heat exchange unit that is disposed around the burner, and a combustion gas discharge unit for discharging the combustion gas having passed through the heat exchange unit is provided.

A heat exchanger comprising a mixture inflow unit into which a mixture of air and fuel is introduced, a burner for combusting the mixture introduced through the mixture inflow unit, a heat exchange unit that is disposed around the burner, and a combustion gas discharge unit for discharging the combustion gas having passed through the heat exchange unit is provided.

A water heating pod includes at least one water heating module packaged within a container. The water heating module includes a plurality of water heating units in fluid communication with a basin. The basin is configured to support a first fluid communication between the water heating units and provide a second fluid isolation between the water heating units.

A water heating pod includes at least one water heating module packaged within a container. The water heating module includes a plurality of water heating units in fluid communication with a basin. The basin is configured to support a first fluid communication between the water heating units and provide a second fluid isolation between the water heating units.

A heat exchanger for hot water supply (21) is comprised of: a first heat exchanging unit (21) a that heats the water, which is supplied from a second communication section x.sub.1 to the hollow portions of hollow plates P.sub.1 to P.sub.5 and reaches a first communication section y, by a combustion exhaust gas that circulates through the gaps among the hollow plates P.sub.1 to P.sub.5; and a second heat exchanging unit (21b) that heats the water, which is supplied from the first communication section y to the hollow portions of the hollow plates P.sub.6 to P.sub.8 below the hollow plates P.sub.1 to P.sub.5 and reaches a third communication section x.sub.2, by a heat medium that circulates through the gaps among the hollow plates P.sub.6 to P.sub.8.

A waste heat extraction and capture device located in a stream of waste heat from a cooking appliance extracts heat energy from heated air destined for venting to an ambient exterior. A heat transfer element disposed in a vent hood above the cooking surface recovers heat for recapturing thermal energy that would otherwise be simply expelled. A fluid traveling through the heat transfer element is heated by the passing exhaust stream of waste heat, and can be stored for subsequent use, such as for potable hot water, interior space heating, or other cooking processes. An attachment strap, bracket or mechanism secures the heat transfer element in the vent hood that is typically tapered for effective heat gathering, and is positioned downstream of filters or traps for grease so as to avoid clogging the heat transfer element.

A waste heat extraction and capture device located in a stream of waste heat from a cooking appliance extracts heat energy from heated air destined for venting to an ambient exterior. A heat transfer element disposed in a vent hood above the cooking surface recovers heat for recapturing thermal energy that would otherwise be simply expelled. A fluid traveling through the heat transfer element is heated by the passing exhaust stream of waste heat, and can be stored for subsequent use, such as for potable hot water, interior space heating, or other cooking processes. An attachment strap, bracket or mechanism secures the heat transfer element in the vent hood that is typically tapered for effective heat gathering, and is positioned downstream of filters or traps for grease so as to avoid clogging the heat transfer element.

A heater comprises an inlet for a medium to be heated, an outlet for the medium, and at least two cassettes. Each cassette comprising a first plate comprising a first main surface and a second plate comprising a second main surface. The first and second plates are attached to each other and enclose a respective flow channel for the medium. The cassettes are arranged beside each other with a space between the cassettes for an electric heating element. The electric heating element abuts the first main surface of one of the cassettes and the second main surface of the adjacent cassette. The heater comprises two distance members extending between the one cassette and the adjacent cassette. The distance members define the space.

A heat exchanger comprising a mixture inflow unit into which a mixture of air and fuel is introduced, a burner for combusting the mixture introduced through the mixture inflow unit, a sensible-heat exchange unit that is disposed around the burner, a latent-heat exchange unit in which heat is exchanged between combustion gas having passed through the sensible-heat exchange unit and a heating medium, and a combustion gas discharge unit is provided.