To provide a manufacturing method of a heat exchanger for a fuel cell, capable of removing residue flux remaining inside the heat exchanger in a short time, and preventing elution of the residue flux to a circulating water.
In a residue flux removing process S5, an alkali cleaning process S6 with alkali cleaning liquid injected into a flow channel of a core part 20 for cleaning, an acid cleaning process S8 with acid cleaning liquid injected into the flow channel, a physical treatment process S10 physically removing the residue flux, and a warm pure water cleaning process S13 with warmed pure water injected into the flow channel for cleaning, are combined. By combining the above processes, residue flux cleaning time can be drastically reduced.
KUBO KENJIRO
NAKANISHI HISANORI
NEOS KK
Iwa Saki Kokuni
Kawamata Sumio
Masakazu Ito
Shunichi Takahashi
Toshio Takamatsu