REMKO Fin-tube heat exchanger - Manual (Page 10)

10
REMKO
FIN-TUBE HEAT EXCHANGER
General Information
■ Do not continually top up the water
level in the storage tank. This will
prevent corrosion damage to the tank.
■ In hard water areas, connect a
standard descaling device upstream
of the tank.
Installation
Electrically insulated installation
electrically insulated connecting fittings
To protect inadequately coated areas
against corrosion, magnesium anodes
or external current anodes are generally
installed in enamelled or in plastic clad
steel hot water tanks.
This protection against corrosion
provided by the use of cathodes
becomes problematic if heating coils
that are not insulated are also installed.
Heating coils that are not insulated
quickly consume the anodes. The
defective areas form a galvanic element
together with the valuable heating coil
materials that can cause the defective
area's substrate to decompose.
Insulating connecting fittings prevent
this galvanic element from forming and
in this way provide significant protection
against corrosion in coated steel hot
water tanks.
A protective current bleeder resistor is
installed to protect the fin-tube heat
exchanger against current-induced
corrosion.
The insulated connections use insulate
the heating coils both against the tank
wall and against the metal connecting
lines and comply with DVGW data sheet
specifications.
W 511.
Protection against corrosion when using
different metals in the installation
The resistance of copper to corrosion
caused by contact with drinking water
is long proven. Copper has proven itself
as a working material especially given
the fact that chlorine is often present in
drinking water.
The heat transmitters also comply with
the requirements specified by DIN 1988
and DIN 4753.
When copper comes into contact with
water, copper ions are released to the
water.
Copper pipes do not pose a problem
because a dense, strongly adhering
top layer quickly forms.
In galvanised steel pipes installed down-
stream however, the released copper ions
can quickly cause corrosion.
To prevent corrosion when different
metals are used in the installation, the
outside of the heating coils is galvanically
tin-plated.
Installation may only be performed
by authorised specialists.
NOTE