Approved Corrosion Inhibitors And Anti-Freeze Fluids For Central Heating Water; Frost Protection; Sealing Agents; Summary Of Bdh Information Sheet On Identifying Corrosion By Cfcs - Benchmark CS1 Installation And Servicing Instructions

4.4 Approved corrosion inhibitors and
anti-freeze fluids for central
heating water
If any system water treatment is required then
only products suitable for use with Aluminium
shall be used i.e Fernox- Copal or Superconcen-
trate or Sentinal X100, in accordance with the
manufacturers instructions. The use of any other
substances will invalidate the guarantee. The pH
value of the system water must be less than 8 or
the appliance guarantee will be invalidated.
4.4.1

Frost protection

B Add a suitable anti-freeze fluid to the water in the
central heating system.
Suitable products are available from Betz-Dearborn
Tel.: 0151 4209563, Fernox Tel.: 01799 550811
and Salamander Tel.: 0121 378 0952.
4.4.2

Sealing agents

B In our experience, the addition of sealing agents to
the water in the central heating system can cause
problems (deposits in the heat exchanger). For that
reason we advise against their use.
7 181 465 346 GB (03.02)
4.5 Summary of BDH Information
Sheet on Identifying Corrosion by
CFCs
The presence of halogenated hydrocarbons in the com-
bustion air causes surface corrosion on affected met-
als. Particularly susceptible is the combustion chamber
and the heat exchanger surfaces (including stainless
steel) as well as the metal components in the flue
socket, flue pipe connections and in the chimney.
The halogen compounds present in the combustion air
produce highly corrosive hydrochloric acid in the flame
and in some cases - depending on the precise compo-
sition of the combustion air - hydrofluoric acid, both of
which accumulate in the boiler and remain active over
long periods.
In order to limit the damage, the source of the air con-
tamination must be located and sealed off. If this is not
possible, the combustion air must be drawn from an
alternative clean source.
Halogens can occur in the following locations:
Commercial and industrial sources
Dry cleaners Trichloroethylene, tetrachlo-
roethylene, fluorinated hydro-
carbons
Degreasing baths Perchloroethylene, trichlo-
roethylene, methyl chloroform
Printers Trichloroethylene
Hairdressers Aerosol spray propellants,
hydrocarbons containing fluo-
rine and chlorine (freons)
Sources in the home
Cleaning and Perchloroethylene, methyl
degreasing chloroform, trichloroethylene,
agents methylene chloride, carbon
tetrachloride, hydrochloric
acid
Home workshops
Solvents and thin- Various chlorinated hydrocar-
ners bons
Spray cans Chlorofluorohydrocarbons
(freons)
Table 14
Appendix
55