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The smallest internal diameter of the open safety pipe and the supply and
expansion pipes can be calculated as follows:
Safety flow (expansion) pipe: d
G
= 15+1.4 b
9
mm (but it cannot be smaller than
19 mm).
Safety return (supply) pipe: d
D
= 15+1.0 b d
m m
9
: It is the boiler's
nominal heat output in kW. (do not forget symbols)
Operational requirements of open expansion systems;
For safe and economic operation of open expansion systems, the following
controllers must be available in the system.
Water level gauge;
The hydrometer must be connected to the system to show the water level in the
heating system as a meter water column.
Water temperature gauge (thermometer);
The boiler must be more than 20% of its maximum operating temperature. The
boiler must be installed in the flow line (the water temperature gauge in the
boiler return line is not required by the standards but is recommended by us).
All optional boiler control panels have a water temperature gauge (Boiler
thermometer). If the optional control panel is not supplied, water temperature
gauge must be supplied and installed by the installer.
Water temperature controller (Boiler thermostat);
There must be a controller which controls and regulates the water temperature
required by the heating system. This temperature cannot be above the
adjustable maximum setting temperature of the controller, boiler operating
temperature. For stand
ard CGS2 and CGS3 boilers max. 90°C. All optional
boiler control panels have a water temperature controller (Boiler thermostat). If
the optional control panel is not supplied, this controller must be supplied and
installed by the installer.
There must be a ventilation system suitable for the total boiler capacity in the
boiler room in order to be able to expel toxic, explosive gases that may occur in
the boiler room and ensure an efficient and low emission combustion. It must be
ensured that this ventilation system is functional as long as the boiler is active.
Ventilation calculations must be calculated according to the local directives.
