17
Danger!
Never stand in front of the boiler door while opening.
Hint!
During the cold boiler's start-up, condensation of water vapour
on walls can occur. The so-called boiler's sweating gives the
impression of leakage. It is a natural phenomenon, which
disappears after heating up the boiler to a temperature
exceeding 60°C. In
the case of a new boiler, depending on
atmospheric conditions and the boiler's water temperature, this
may last for a few days.
Picture 16. Correct position of fuel in the combustion chamber.
The position of a flap dosing the air in the ash-pan and furnace doors
should be set using the string of draught regulator to obtain the required
thermal efficiency and required temperature in the boiler.
If the fire goes out while starting up, the furnace is to be cleared, the
boiler's channels are to be vented and the start-up procedure is to be
restarted.
A thermal power regulator (draught regulator) is supplied in installed
condition with a boiler in a horizontal position. A white scale for the setting
of the required temperature is used in the horizontal position. Adjust the
length of the chain connecting the flap in the furnace and ash-pan doors
with draught regulation during the first start-up of the boiler. The Draught
regulator setting is based on a setting the temperature of 60 °C (white
scale) using a regulator’s knob. When
the water temperature in the boiler
reaches 60 °C and after
a few minutes of stabilization you should adjust
the length of the chain to ensure that the flow damper for primary air is
lifted by approx. 1 mm and the chain is tensioned.
The setting of the too low temperature of boiler operation (below
55°C) should be avoided because it influences worsening of
the
combustion process and increased the emission of noxious compounds
to the environment. Condensation phenomenon occurs on boiler walls
(“sweating”)
in the case when the boiler is operated at a low temperature.
Long-term maintaining of this phenomenon is a reason for increased
corrosion and shortening of boiler lifetime. That is why relatively high
operation temperature should be set, while the temperature in rooms
should be adjusted using thermostatic heating valves. It is also
recommended to use mixing valves.
Fuel burning period depends on its quality and quantity, therefore the
user should experimentally determine the size of charging and starting-up
fire time for his own convenience. During normal work, the control
process consists of a periodical filling of the furnace chamber with fuel.
Refilling and firing up of fuel in the furnace chamber is possible after
complete burning out of a portion of the fuel and unloading of the
accumulation tank.
Complete ash removal is performed manually, after damping a boiler.
Lumped fuel combustion products such as slag, stone and sinter should
be removed using tools, after damping and cooling of the boiler or before
start-up.
Burn risk.
Note!
Be particularly careful during opening of the boiler’s doors.
Note!
Operation of the
boiler with temperatures exceeding 65°C
effectively prevents the creation of condensate and accelerated
corrosion of the boiler.
Hint!
Only genuine spare parts purchased from DEFRO R. Dziubeła
sp. k. can be used.
DEFRO R. Dziubeła sp. k. does not accept liability for incorrect
work of boilers caused by incorrect parts.
Note!
It is forbidden to operate the boiler if the ceramic components
in the combustion chamber have been damaged.
Before restarting the operation of the boiler, it is absolutely
required to restore the device to the factory settings.
8.4 LOW-TEMPERATURE CORROSION.
The boilers should be operated with differences between supply and
return temperatures within the range of 10-
20°C and return water
temperature not smaller than 55°C. While
the operation of the boiler, if the
central heating water temperature is below 60°C, results in condensation of
water vapour contained in flue gas condenses on boiler's walls. During the
initial period of operation, the above-mentioned condensate may leak from
the boiler onto the floor in the boiler room.
Longer operation at a lower temperature may lead to corrosion resulting
in a shorter boiler's life. Hence, it is not recommended to use the boiler if the
temperature of water supplying the central heating syst
em is below 60°C.
To ensure the proper, failure-free and effective operation of the boiler it
is recommended to operate the boiler on 80% of its rated power and
temperature on a boiler minimum of
65°C. It
is also recommended to install
a mixing valve.
Note!
If the temperature of water supplying the central heating system
is below 60°C, boiler operation leads to intensified precipitation
of tarry substances from burnt fuel resulting in deposits of tar
sludge in the heat exchanger and flue, which leads to the risk of
soot ignition in the chimney.
8.5.
DAMPING A BOILER
Boiler damping will take place automatically when the fuel burns out. To
damp a boiler before the fuel burns out it is possible to:
• using supplied tools user can, being particularly careful, remove heat from
the
furnace’s grate to
the ash-pan.
• remove heat from ash
-pan to heat-resistant container with cover,
• after several dozen
- few dozes minutes user should check whether
furnace there is no autogenous firing up!
Fuel should be removed from the boiler if the standstill will be longer
than two days and always after the heating season and the boiler should be
left with lifted doors. After the heating season or during a longer period of
boiler non-usage it should be completely cleaned.
8.6.
PERIODICAL SERVICE OF BOILER - CLEANING AND MAINTENANCE.
Hint!
In the case of fluctuations of the chimney draught and when
the smoke escapes from the boiler (from the flow damper in the
charging doors) it is required to close the primary air flow
damper (flap) in the ash-pan and furnace doors, reducing the
temperature set on the draught regulator (maintaining the
minimum gap - by locking with adjusting screw), and
secondary air flow damper in charging doors should be set to
open position at 50%.
Danger!
Furnace chamber and ash-pan should always be closed,
except of the start-up period, charging and removal of
combustion wastes.
Hint!
In order to maintain satisfactory combustion efficiency, the
convection channels and sheets in the furnace chamber are to be
clean. Soot, dust and ash created as a result of combustion
reduce the effectiveness and efficiency of the combustion
process.
Danger!
Certain elements of the boiler can reach the temperature of
400°C! In order to clean the boiler
, it is necessary to switch it off
and wait the necessary period of time required to decrease of heat
exchange surface temperature.
Danger!
Any service and maintenance works are to be carried out with
meticulous care and only by adults. The boiler should not be
cleaned in the presence of children. To carry out any tasks,
protective gloves, glasses and headgear are to be worn.
Set the short cycle lever to
OPEN
, then carefully lift the doors and open
them after equalisation of the pressures.
Set the secondary air flow damper (pic. 3, pos. 4) to
CLOSED
position
and short cycle lever to
OPEN
position when the furnace and ash-pan
doors are being opened. Then, carefully lift the doors and open them
after equalisation of the pressures.
100 mm
100 mm
