ROC COMBI HE 2802 - Flushing and Water Treatment

16
Shower
Any shower valves used with the appliance
should be of a thermostatic or pressure
balanced type. Refer to the shower
manufacturer or performance guidance and
suitability.
Flushing and Water Treatment
The boiler is equipped with a stainless steel
heat exchanger.
The detailed recommendations for water
treatment are given in BS 7593:2006
(Treatment of water in domestic hot water
central heating system); the following notes
are given for general guidance.
If the boiler is installed on the existing system,
any unsuitable additives must be removed.
Under no circumstances should the boiler be
red before the system has been thoroughly
ushed; the ushing procedure must be in line
with BS 7593:2006.
We strongly recommend the use of a ushing
detergent appropriate for the metals used in
the circuit. These include cleansers produced
by Fernox and Sentinel, Whose function is to
dissolve any foreign matter that may be in the
system.
In hard water areas or where large quantities
of water are in the system the treatment of
water to prevent premature scaling of the main
heat exchanger is necessary.
The formation of scale heat compromises the
efciency of the thermic exchanger because
small areas of scale cause a high increase
of the temperature of the metallic walls and
therefore add to the thermal stress of the heat
exchanger.
Deminieralised water is more aggressive so in
this situation it is necessary to treat the water
with an appropriate corrosion inhibitor.
Any treatment of water by additives in the
system for frost protection or for corrosion
inhibition has to absolutely suitable for all
metals used in the circuit.
The use of a corrosion inhibitor in the system
such as Fernox MB-1, Sentinel X100 or
Fernox system Inhibitor is recommended
to prevent corrosion (sludge) damaging the
boiler and system;
If anti-freezing substances are to be used
in system, check carefully that they are
compatible with the metals used in the circuit.
ROC suggests that use of suitable anti-freeze
products such as Fernox, which will prevent
rust and incrustation taking place.
Periodically check the PH balance of water/
anti-freeze mixture of the boiler circuit and
replace it when the amount measured is out
of range stipulated by the manufacturer (7<
pH < 8). DO NOT MIX DIFFERENT TYPES OF
ANTI-FREEZE
In under-floor heating system, the use of
plastic without protection against penetration
of oxygen through the walls can cause
corrosion of the systems metal parts (metal
piping, boiler etc.) through the formation of
oxides and bacterial agents.