Noritz Corporation

Hideaki Yoshitomi

Tetsurou Hamada

Kozo Uehara

Hitoshi Hara

Hiroaki Takashima

Yoshinori Kanda

Mitufuku Asakawa

A first period during which drain is not substantially generated on a surface of a water tube () of a heat exchanger (B), and a second period as a transition during which an amount of drain on the surface of the water tube () is increased are provided. There are a plurality of kinds of fan-controlling data in which operation control contents of the fan () in the first and second periods in correspondence with change of conditions of entering water temperature or combustion level of the burner (). The fan-controlling data are stored in a data table () of a controller (). The controller () controls the fan () in accordance with the data, and an initial air-fuel ratio of combustion driving of the burner () is stabilized.

Water heater

A heat exchanger Aincludes a partitionpartitioning the spacesurrounded by a coiled tubeat an axially intermediate portion of a housinginto a first and a second regionsandand partitioning the coiled tubeinto a first and a second heat exchanging portions HTand HT. The combustion gas supplied to the first regionflows to a combustion gas pathby passing through a clearanceof the first heat exchanging portion HTand then passes through a clearanceof the second heat exchanging portion HT. With this structure, the amount of heat recovery is increased, and the heat exchange efficiency is enhanced while simplifying the overall structure of the heat exchanger Aand reducing the size of the heat exchanger.

Heat exchanger and water heater

A heat exchanger Aincludes a coiled tubeincluding a plurality of loopsand a spacesurrounded by the coiled tubeand having an end closed by a partitionThe heat exchanger is so designed that combustion gas flows from the spaceto a combustion gas pathby passing through clearancesof the loopsof the coiled tubeThe loopsare made of a tube having a thickness tand a width Lwhich is larger than the thickness, so that the amount of heat recovery when the combustion gas passes through the clearancesis large. Therefore, the heat exchange efficiency is enhanced while simplifying the overall structure of the heat exchanger Aand reducing the size of the heat exchanger.

Growing community of inventors

Hyogo, Japan

Hideaki Yoshitomi