A condensing gas boiler having a corrosion prevention structure of preventing
corrosion
caused by using heterogeneous metal is provided, which includes a casing provided
with a combustion chamber therein; a present heat exchanger arranged in the casing,
which includes a first tubular tube made of a copper material having a plurality
first thermal pins formed by processing an outer circumferential surface; a latent
heat exchanger disposed at a distance from the present heat exchanger, which includes
a second tubular tube whose inner portion is made of a copper material and whose
outer portion is made of aluminum, having a plurality second thermal pins formed
by processing an outer circumferential surface; end plates contacting and engaged
with each other while the present heat exchanger and the latent heat exchanger
are fixedly arranged in respective rows and installed in the casing; and a plurality
of connection tubes which are mutually connected through a connection portion so
that water can circulate through the present heat exchanger and the latent heat
exchanger, wherein connection tubes which are made of a corrosion-resistant material
are installed to have a broader area, and simultaneously connection tubes which
are made of a corrosion-easy material are installed to have a smaller area, to
thereby suppress galvanic corrosion through an unfavorable area ratio, and wherein
an insulator for electrical insulation is provided between the end plates. Galvanic
corrosion or stay current corrosion caused by using heterogeneous metal between
the present and latent heat exchangers is suppressed, to thereby enhance durability
of a product and thus heighten reliability of the product.
