INSTALLATION AND HYDRAULIC PLANT SAFETY DEVICES
During installation of the boiler it is MANDATORY to insert
a manometer into the system in order to display the water
pressure. The installation, relative system connections,
commissioning and inspection of correct functioning must
be carried out perfectly, in total compliance with Standards in
force, both national, regional and municipal, as well as these
instructions.
For Italy, installation must be carried out by professionally
authorised staff (Ministerial Decree dated 22.01.08 n°37).
The company declines all responsibility for damage/injury
to objects and/or persons caused by the system.
SAFETY DEVICES FOR CLOSED VESSEL SYSTEM
According to the UNI 10412-2 (2006) Standard in force in
Italy, the closed systems must have: safety valve, pump
control thermostat, acoustic alarm activation thermostat,
temperature indicator, pressure indicator, acoustic alarm,
regulation automatic circuit breaker switch, automatic circuit
breaker block switch (block thermostat), circulation system,
expansion system, safety dissipation system incorporated
with the generator with thermal safety valve (self-activated),
whenever the appliance does not have a temperature self-
adjustment system.
DISTANCES OF SAFETY DEVICES ACCORDING TO THE
STANDARD
Component
Temperature safety sensors
Missing devices because not
as per standard
The temperature safety sensors must be in place on the
machine at a distance no greater than 30 cm from the fl ow
connection.
Whenever the generators lack a device, those missing can
be installed on the generator fl ow pipe, within a distance no
greater than 1m from the machine.
The domestic heating appliances with automatic feeding
must: be supplied with a fuel block thermostat or be supplied
with a cooling circuit set-up by the appliance manufacturer.
The cooling circuit must be activated by a heat safety valve
such to guarantee that the limit temperature set by the
Standard is not exceeded.
Connection between the power supply unit and the valve
must be free from interceptions.
The pressure upstream from the cooling circuit must be at
least 1.5 bar.
HYDRAULIC PLANT
Certain concepts referring to the Italian UNI 10412-2 (2006)
Standard are described in this chapter. As previously described,
when installing, all national, regional, provincial and town
council Standards in force provided by the country in which
the appliance has been installed must be complied with.
INSTALLATION AND HYDRAULIC PLANT SAFETY DEVICES
Distance
On the machine or not
exceeding 30 cm
Not exceeding one metre, on
the fl ow pipe
TYPE OF SYSTEM
There are two diff erent types of system: open vessel system and
closed vessel system. The product has been designed and realised
to work with closed vessel systems.
CLOSED VESSEL SYSTEM FOR AUTOMATIC LOADING
APPLIANCES
System in which the water it contains is not in direct or indirect
communication with the atmosphere. Generally, the closed
vessel system has one of the following expansion vessels:
Pre-loaded closed expansion vessel with membrane
impermeable to the passage of gases.
Automatic closed expansion system with compressor
and membrane impermeable to the passage of gases.
Automatic closed expansion system with transfer pump
and membrane impermeable to the passage of gases.
Expansion system without diaphragm.
COMMISSIONING CHECKS
Before connecting the boiler:
a) wash all system piping in order to remove any residues
which might compromise the correct functioning of certain
system components (pumps, valves, etc.).
b) check to verify that the fl ue has adequate draft, is not
narrowed and that other appliances do not discharge into the
fl ue.
Only after this control can the chimney fi tting between the
boiler and fl ue be mounted. It is recommended to control the
fi ttings with pre-existing fl ues.
FEEDING WATER FEATURES
The chemical-physical features of the system and reinstate
water are fundamental for the correct functioning and life-
span of the boiler.
Amongst the inconveniences caused by bad quality feeding
water, the most frequent is the scaling of the heat exchange
surfaces.
Less frequent, but equally serious, is the corrosion of the water
side surfaces of the entire circuit.
It is known that the lime scale, even if there is only a few
millimetres, due to their low thermal conductivity, greatly
reduce the heat exchange, determining damaging localised
heating. It is strongly recommended to treat the water in the
following cases:
a) very hard water available (higher than 20°f )
b) very extended systems
c) large water quantities restored due to leaks
d) subsequent fi llings due to system maintenance work
It is recommended to always contact specialised companies to
treat the feeding water of the heating systems.
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