A condensation tray for condensing tankless water heaters is disclosed. The tray can include a plurality of peaks and valleys. The peaks can divert condensate runoff from a secondary heat exchanger into the valleys so as to prevent the condensate from falling on a primary heat exchanger. The tray includes gas apertures that enable combustion gases to pass through the tray and across the secondary heat exchanger. Overhangs on the peaks can prevent the condensate from draining through the gas apertures.

A condensation tray for condensing tankless water heaters is disclosed. The tray can include a plurality of peaks and valleys. The peaks can divert condensate runoff from a secondary heat exchanger into the valleys so as to prevent the condensate from falling on a primary heat exchanger. The tray includes gas apertures that enable combustion gases to pass through the tray and across the secondary heat exchanger. Overhangs on the peaks can prevent the condensate from draining through the gas apertures.

A heat exchanger tube for transferring a heat of an exhaust gas to a fluid to be heated includes a turn-back portion formed in an intermediate portion of the heat exchanger tube and a reciprocating conduit portion. The reciprocating conduit portion includes a conduit portion leading from a starting end of the heat exchanger tube to the turn-back portion, and a conduit portion leading from the turn-back portion to a terminal end of the heat exchanger tube. A space equal to or greater than the outer diameter of the conduit portions is provided between these conduit portions.

A heat exchanger tube for transferring a heat of an exhaust gas to a fluid to be heated includes a turn-back portion formed in an intermediate portion of the heat exchanger tube and a reciprocating conduit portion. The reciprocating conduit portion includes a conduit portion leading from a starting end of the heat exchanger tube to the turn-back portion, and a conduit portion leading from the turn-back portion to a terminal end of the heat exchanger tube. A space equal to or greater than the outer diameter of the conduit portions is provided between these conduit portions.

A condensate collector (40) for use in water heating apparatus (10). The apparatus (10) includes a liquid storage tank (12), a combustion chamber (20), a flue (26) disposed above the combustion chamber (20), and, a condensate collector (40). The condensate collector (40) includes a receptacle (42) positioned in an entry end (28) of the flue (26), a discharge outlet (53) for discharging condensate collected in the receptacle (42) for subsequent transfer to a drain.

A heat exchanger unit according to the present invention includes a sensible heat exchanger including a sensible heat exchange pipe disposed in a sensible heat exchange area for heating water used for heating by receiving sensible heat generated by a combustion reaction, wherein the sensible heat exchange pipe receives the water used for heating and flows same through the interior, and a sensible heat fin disposed in the sensible heat exchange area. The sensible heat fin is formed in a plate shape across the sensible heat exchange pipe and penetrated by the sensible heat exchange pipe; and a latent heat exchanger positioned downstream from the sensible heat exchange area on the basis of a reference direction, which is a flow direction of combustion gas generated during the combustion reaction, the latent heat exchanger including a latent heat exchange pipe disposed in a latent heat exchange area.

A heat exchanger unit according to the present invention includes a sensible heat exchanger including a sensible heat exchange pipe disposed in a sensible heat exchange area for heating water used for heating by receiving sensible heat generated by a combustion reaction, wherein the sensible heat exchange pipe receives the water used for heating and flows same through the interior, and a sensible heat fin disposed in the sensible heat exchange area. The sensible heat fin is formed in a plate shape across the sensible heat exchange pipe and penetrated by the sensible heat exchange pipe; and a latent heat exchanger positioned downstream from the sensible heat exchange area on the basis of a reference direction, which is a flow direction of combustion gas generated during the combustion reaction, the latent heat exchanger including a latent heat exchange pipe disposed in a latent heat exchange area.

A water heater according to the present invention includes: a heating unit that includes a burner provided to cause a combustion reaction from air and fuel, and that is provided to generate heated water by using heat generated by the combustion reaction; and a humidifier unit that generates water steam by evaporating water using a combustion gas generated by the combustion reaction and discharged from the heating unit, and provides the water steam together with the air to the burner.

A heat exchanger for heating a fluid flowing through a pipe using a combustion gas includes: a body including open upper and lower ends and having a space formed therein to allow the combustion gas to pass therethrough; a combustor formed in an upper portion of the space in which combustion of the combustion gas occurs; a heat exchange portion formed below the combustor and provided with a heat exchange pipe configured to heat an internal fluid by using the combustion gas; and a heat return pipe provided outside the space so as to be in contact with an outer surface of the body, wherein the combustor and the heat exchange portion may be unitarily formed, and the body in which the combustor is formed includes a concave portion protruding concavely inward so as to correspond to a shape of an outer circumferential surface of the heat return pipe.

A heat exchanger for heating a fluid flowing through a pipe using a combustion gas includes: a body including open upper and lower ends and having a space formed therein to allow the combustion gas to pass therethrough; a combustor formed in an upper portion of the space in which combustion of the combustion gas occurs; a heat exchange portion formed below the combustor and provided with a heat exchange pipe configured to heat an internal fluid by using the combustion gas; and a heat return pipe provided outside the space so as to be in contact with an outer surface of the body, wherein the combustor and the heat exchange portion may be unitarily formed, and the body in which the combustor is formed includes a concave portion protruding concavely inward so as to correspond to a shape of an outer circumferential surface of the heat return pipe.