FLUID HEATER.

摘要

This invention consists in radiant heat in a fluid heater having an increased area for receiving radiant heat in a high energy density structure which is easy in maintenance and capable of preventing entrance of contamination source. For attaining the object, a transparent internal pipe (11) of a fluid heating pipe unit opening at both ends is arranged in an external pipe (12) of said unit having an inlet and outlet for fluid flow on the wall thereof in such manner that the former may be spaced from the inner wall of the latter, both pipes (11, 12) are sealingly connected to each other at respective ends, and an electric heater (2) is arranged in the internal pipe while spaced from the inner wall of said pipe and is supported by supporting members (91, 92) at both ends.