Closed Expansion Vessel; Commissioning Checks; Automatic Thermostatic Mixer Valve Mandatory - Extraflame HP 15 Benutzerhandbuch

valve inlet or than the sum of the inlet cross-sections, in the event of several valves serving a single pipe. The discharge piping
of the safety valve must be realised in order not to prevent the regular functioning of the valves and not to cause damages to
persons; the discharge must ow immediately near the safety valve and be accessible and visible. The diameter of the discharge
piping must not however be lower than that of the outlet connection of the safety valve. For diameter of outlet connection it is
intended the minimum internal diameter on the valve outlet upstream of the eventual internal threading.

CLOSED EXPANSION VESSEL

Warnings: check that the preload of the expansion vessel is set to 1.5 bar.
The vessel maximum exercise pressure must not be lower than the calibration pressure of the safety valve, increased by
overpressures, characteristic of the same valve, bearing in mind the eventual level di erence between vessel and valve and
the pressure generated by the functioning of the pump. The capacity of the expansion vessel/s is evaluated depending on the
total system capacity as results from the project. The closed expansion vessels must comply with the provisions concerning the
design, manufacturing, conformity assessment and use of pressure appliances. Intercepting objects or section decreases must
be inserted/practiced on the connection piping, which can be constituted by system portions. The insertion of a three-way
intercepting valve which allows connection between the vessel and the atmosphere for maintenance Operations, is allowed.
Such device must be protected against accidental manoeuvres. The connection pipe must be realised in order not to present
scales or deposits storage points. In case of more heat generators which feed the same plant or the same secondary circuit, each
heat generator must be connected directly to the expansion vessel or plant expansion vessels unit, altogether dimensioned
for the total volume of water contained in the same plant or the same independent circuit. Where it is necessary to separate
the individual heat generator from the expansion vessel or expansion vessels unit, a three-way tap must be applied on the
connection piping between the generator and the vessel, in order to ensure, in every position, the connection of the generator
with the expansion vessel or with the atmosphere. The expansion vessels, the connecting pipes, the bleed pipes and drain pipes
must be protected from freezing, where this phenomenon occurs. The solution used for this purpose is described in the design.

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 ue has adequate draft, is not narrowed and that other appliances do not discharge into the ue.
This is to prevent unexpected power increases. Only after this control can the ue tting be mounted between the boiler and
the ue. A check of the connections with pre-existing ues is recommended.

AUTOMATIC THERMOSTATIC MIXER VALVE MANDATORY

It is required to create an adequate anti-condensation circuit that ensures a return temperature for the appliance of at least 55°
C. The anti-condensation valve, for example, is applied in solid fuel boilers as it prevents the return of cold water in the heat
exchanger.
Routes 1 and 3 are always open and, together with the pump
installed on the return, they guarantee water circulation
inside the biomass boiler exchanger.
A high return temperature allows e ciency improvement,
reduces formation of smoke condensation and prolongs the
life span of the generator.
Valves on the market have di erent calibrations. The manufacturer
advises use of model 55°c with 1" hydraulic connections.
Once the valve calibration temperature is reached,
route 2 is opened and the boiler water goes to the system via
the ow.
52
1
Valve sold as an accessory (optional)
ENGLISH
3
2