Unical TERNOx 2S, Инструкции по установке, использованию и обслуживанию, Страница: 43 / 48

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Maintenance instructions
3.24 - CHECKS DURING AND AFTER
COMMISSIONING
When the appliance has been commissioned, check that it
performs a shutdown and subsequent ignition:
- by modifying the boiler thermostat calibration;
- by intervening on the main switch of the panel board.
Check tightness of all the gaskets on the water and flue gas
side. They must be further tightened when hot to guarantee
perfect sealing.
This operation is crucial for the gasket of the
doors, of the burner plate and of the flue gas
casing so that toxic and dangerous combustion
fumes do not escape from the boiler room.
Then tighten them when hot to guarantee
perfect sealing.
3.25 - ALKALINE
OR “BOILING” WASH
This is a treatment carried out by specialised companies on
the new boiler.
It removes deposits consisting of residual oil, grease and metal
oxides caused by processing and assembly of the boiler.
If these substances are not eliminated, corrosion is caused due
to the obstruction of the formation of a passivation coating on
surfaces exposed to water.
Execution of alkaline wash:
- Fill the boiler with water.
It is also very important to check sealing of the boiler/chimney
fitting for the reasons expressed above.
It is also extremely important to progressively tighten the gasket
of the railing and manhole of the generator as the temperature
increases for perfect sealing: otherwise the first time it leaks,
the gasket would need to be replaced.
Check that the appliance fully stops when acting on the main
switch of the system.
After all these conditions have been met, the burner must
be properly calibrated at the maximum output allowed by the
boiler, analysing the flue gas to achieve correct combustion and
as few polluting emissions as possible.
As the pressure of the water in the system increases during
operation, make sure that its maximum value does not exceed
the design pressure of the boiler.
- Instruments (pressure switch, pressure gauge etc.) must be
excluded before starting the wash.
- Introduce 0.3 to 1% of caustic soda, sodium carbonate or
trisodium triphosphate into the total content of the water.
- Specific surfactants must be added to these substances
ranging from 0.05 to 0.15% of the total content of the water.
- Switching on the burner, bring the water to a temperature of
80-90°C and have it circulate in the boiler for 12-14 hours.
- Slowly empty the content and simultaneously introduce cold
water to rinse it properly.
3.26 - BOILER SHUTDOWN
To shut down the boiler for a long period, proceed as follows:
- perform the preservation procedure of the water side, which
can be wet or dry;
- turn off the main switch of the electric panel and disconnect
the power supply;
- close the fuel shut-off valve;
- perform the flue gas side preservation procedure;
- protect all control, adjustment and safety devices from dust
and humidity.
"Wet preservation" entails completely filling the boiler and
adding preserving or neutralising products to the water.
Then the system must be sealed by closing all the shut-off
valves.
This type of preservation is not recommended if there is a risk
of freezing.
"Dry preservation" requires emptying the boiler.
Open the railing, completely dry the inside of the boiler by
blowing air and insert highly hygroscopic substances (e.g.
quick lime).
Close all the shut-off valves and the railing, thus sealing the
generator.
Preservation of the flue gas side is performed as follows: open
the inspection doors, remove the burner and disassemble the
cap, clean all surfaces from soot (which could contain sulphur
which becomes sulphuric acid when it becomes moist) and
insert highly hygroscopic substances (e.g. quick lime) into the
furnace and flue gas casing.
Hermetically close all the inspection doors, put the burner cap
and burner back in place.