Unical TRIOPREX N Series, Инструкция по установке, использованию и обслуживанию

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13
L
Ø A
2.6 - FURNACE DOOR:
ADJUSTMENT,
OPENING & CLOSING
A special attention has been paied to the
design of the front door, because in all the
pressurised boilers a good quality of the doors
is a necessary condition for the best operation
of the boiler.
2.6.1- IMPORTANT NOTE
Before opening the furnace door it is necessary
to adopt the following precautions:
-
Close the fuel cock (oil or gas) to the burner.
- Cool down the boiler by keeping the water
circulating through it, and only then switch
off the power.
- Put on the boiler a Warning notice with
the following text:
DO NOT USE, BOILER
UNDER SERVICE, OUT OF ORDER.
2.7 - BURNER
2.7.1 - CONFORMITY OF THE BURNER
All the burners equipping the TRIOPREX-N
boilers must be CE certificated and must
conform to the following directives and
standards:
-
Gas Appliances Directive (90/396/CEE);
- EMC Directive (89/336/CEE).
- EN 267 - Automizing oil burners of
monobloc type - Testing -
- EN 676 - Automatic forced draught burners
for gaseous fuels.
2.7.2 - CHOICE OF THE BURNER
The correct choise and the adjustment of the
burner are foundamental for the best operation
of the boiler and then they shall be accurate
and not underevaluated.
The burner will be selected by verifying that
the working diagram (fuel flow rate - pressure
in the furnace) is compatible with the same
features declared for the boiler.
Remember that the smoke side resistance,
i.e. the counterpressure in the furnace, are
referred to "0" draught at the chimney base.
It is also convenient that the burner blast tube
have its length not shorter than that shown
in the above table and that the flame have a
shape suitable to the characteristics of the
TRIOPREX-N furnace.
In fact to better exploit all the heating surface
of the reversed flame furnace it is necessary
to use burners capable to guarantee a long
and narrow flame at all operating conditions
or also at minimum input in case of two stage
fig. 16
TX N 65÷85 132 180
øA
mm
L
mm
132 180
TX N 110÷150
TX N 185÷225 180 180
TX N 300÷380 180 200
or modulating burners.
Too short flames can cause a localized
overheating of the front part of the furnace,
and the combustion products, not sufficiently
cooled down, entering the smoke pipes at a
too high temperature, can cause important
damages to the boiler.
The burner manufacturing companies are able
to supply the flame dimensions developped
by their burners.
More informations are given in the paragraph
"Commissioning".
2.7.3 - BURNER INSTALLATION
Before fitting the burner it is necessary to
verify the position of the tubulators inside the
TX N 500÷730 220 230
smoke pipes: each pipe must have its turbulator
and this one has to be positioned as indicated
in the table on page 30.
When mounting the burner to the boiler front
door, check for soundness around the burner
flange and its gasket.
Each boiler is supplied with a length of ceramic
fibre rope (cross section 25x25 mm).
This rope has to be put around the burner
tube to completely seal the tube and the
hole in the door insulation.
Be careful not to leave fissures between the
burner tube and the hole in the door.
In case a cone, having a diameter larger than
the burner tube, the cone is to be removed
before fitting the burner and refitted later on.
After the burner has been fitted, check that
TX N 840 270 280
TX N 1100÷1320 270 320
TX N 1600÷1900 285 350
2.5.6 - SHUNT PUMP
The TRIOPREX-N boilers must always operate
in forced circulation hot water systems and
with a minimum return temperature of 55 °C.
So, it is suggestable to adopt a shunt pump,
having also an anti-condensation purpose,
installed between the flow and return
connections, upstream an eventual 3 or 4 way
mixing valve.
This pump will be sized according to the
following formula:
Q = P x 22
where Q = Water flow rate in liter/h
P
= Boiler nominal output in kW
and the manometric head 1-2 m w.c.
With the furnace working in positive pressure,
in fact, every minimum fissure could cause a
leakage of high temperature combustion
products, with consequent burning of the
gasket and overheating of the door up to its
permanent deformation.
For these reasons the door structure of the
TRIOPREX-N boilers, in addition to the fact
to be very strong, has also the possibility to be adjusted: it can be lifted, lowered and also
slanted, getting, thus, always the perfect
centering of the sealing gasket.
The special inner lining in ceramic fiber
reduces, furthermore, the time to reach the
boiler steady state condition and then reduces
drastically the formation of condensate at the
boiler start.
BURNER BLAST TUBE DIMENSIONS
BOILER TYPE