Noritz Corporation

Keiichi Amada

Hironao Matsunaga

Shuji Kameyama

Kazuhiro Kimura

Akira Tsutsumi

Nobuhiro Takeda

Hiroshi Asakura

A water tube WT of a heat exchanger B includes a helical tube bodywhich includes a plurality of loopsarranged in the axial direction. At least one of the loopsincludes an inclined tube portion which is inclined with respect to the axial direction and a non-inclined tube portion extending perpendicularly to the axial direction. The inclined tube portion is provided at each of opposite end regions sand sin a width direction crossing the axial direction, whereas the non-inclined tube portion is provided at an intermediate region Sin the width direction. With this structure, the pitch pof the loopsis reduced. Therefore, by increasing the number of loops, high heat exchange efficiency is achieved without considerably increasing the size of the helical tube body

Heat exchanger, water heater and water tube

A secondary heat exchanger B for recovering latent heat from combustion gas includes water tubeseach of which is so inclined that a first endis positioned lower than a second end. Therefore, in draining water from each of the water tubes, water can be caused to flow smoothly into a water-inflow and hot-water-outflow headerA connected to the first ends. The secondary heat exchanger B includes a casingwhich includes an upper walland a bottom wallwhich are so inclined that the inner surfaces thereof extend generally in parallel with the water tubes, and the upper and the lower gapsandhave constant widths sand s. Therefore, the amount of heat recovery from the combustion gas passing through the gapsandcan be increased.

Water heater

Growing community of inventors

Hyogo, Japan

Keiichi Amada