5. Design
Smart Fire boilers feature with compact construction that has common features in case of all models. Most
assemblies are installed inside the casing what provides protection against external factors and mechanical
damages
.
5.1 Design of Smart Fire SF 11, SF 15 and SF 22 boiler
Figure No. 1 and Figure No. 2 demonstrates Smart Fire SF11, SF15 and SF22 boiler, its dimensions and
connection to the central heating system and flue chimney. Figure No. 3, No. 4 and No. 4 include boiler
diagram with the main assemblies.
Inside boiler casing there are two main assemblies: boiler body and fuel supply system. The boiler steel body
includes the following components: combustion chamber, ash-pan chamber, heat exchanger and exhaust
manifold.
The combustion chamber includes the stainless steel burner fitted with automatic cleaning system and
automatic igniter that ensures automatic boiler ignition. The fuel is supplied to the burner from above thanks
to gravitation, using the screw feeder fitted with the valve. Directly under the combustion chamber the ash-
pan chamber is located where ash pan is installed to collect ash from the burner. The rear wall of ash pan
chamber is provided with washout hole that enables cleaning of the lower part of heat exchanger.
Heat exchanger is divided with two vertical water trays that provide gallery for flow of exhaust gases.
Exhaust gases generated during fuel combustion flow upwards through the first gallery to the second gallery
that runs downwards to the lower part of exchanger. Next exhaust gases flow to the third gallery and to the
top part of exchanger and then to exhaust manifold from which flow to the breeching. Exhaust gases flow
through the heat exchanger is forced with the exhaust fan installed inside the exhaust manifold. Air volume
delivered by the fan is controlled with the controller. Heat exchanger is fitted with mechanical cleaning
system that also ensures swirles for exhaust gases also.
The washout hole provided with the flap located on the top of boiler body ensures access to the top part of
heat exchanger, it vertical exhaust gas galleries and the cleaning system.
The second main assembly of the boiler relates to fuel supply system that is the integral part of fuel dispenser
which comprises the part of boiler external casing. It consists of: fuel dispenser, fuel screw feeder along with
the motoreducer and valve. Fuel is fed from the bottom part of dispenser with screw feeder that feeds the fuel
to the valve separating the fuel in the supply system and dispenser from burner flame. After discharge from
valve the fuel is fed directly to the burner inside the combustion chamber. The boiler body is connected to
the fuel supply system with the screw feeder flange.
The front wall of boiler is provided with two masking grilles. Under the lower masking grille there is access
door that ensures access to the combustion chamber and ash-pan chamber. The top masking grille comprises
casing of boiler body. The front wall of fuel dispenser is fitted with the display of boiler controller that
provides the user with information on boiler current status, operating parameters and allows boiler
parameters setup.
Heating water inlet and outlet from the heat exchanger is located on boiler rear wall and is provided with
outer threaded 1” stub pipe. The rear wall of boiler is provided also with exhaust breeching that discharges
exhaust gases to the chimney. The breeching is provided with the exhaust gas temperature sensor and
optionally available Lambda probe. The rear wall of boiler is provided with exhaust fan installed over the
breeching.
The boiler is provided with adjustable feet. After assembly adjustable feet enable boiler levelling in case of
uneven floor. Installed foot increase boiler height by 24mm plus available adjustment range. Adjustment
range: 0 ÷ 10mm
.
SMART FIRE BOILER User Manual
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