BENEKOV K14, Operation And Installation Manual

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4.4. Operation, control and safety features of the boiler
Boiler operation and control is provided by
programmer
– see separate user’s instructions.
Safety features
, which ensure safe operation of the boiler:
•
Emergency thermostat is used to prevent the heating system against overheating. It is set by the
manufacturer
to a temperature of about 95 to 100 ° C which is higher than the desired boiler
temperature. The emergency thermostat is located on the back wall of the boiler in the distribution board
of the programmer.
•
Throttle flap is located between the second and third levels at the top of the fin plate heat exchanger
and is used to control the temperature of flue gases at the boiler outlet.
Boiler K14:
When operating the boiler where the temperature of the flue gases is above 100 ° C, the throttle
flap must be closed which means the flap lever on the top of the boiler must be moved as far back
as possible and secured with the locking bolt. At the beginning of the boiler operation (when the
chimney is cold) or during long-term operation of the boiler at lower output it is recommended to
operate the boiler with a partially open flap so that the temperature of the flue gases does not drop
below 90 ° C. In this case the throttle lever must be moved forward and secured by the locking
bolt.
Boilers K20 and K25:
When operating the boiler where the temperature of the flue gases is above 100 ° C, the throttle
flap must be closed which means the flap lever on the side of the boiler must be turned as far as
possible upwards (forwards) and secured by the locking bolt At the beginning of the boiler
operation (when the chimney is cold) or during long-term operation of the boiler at lower output, it
is recommended to operate the boiler with a partially open flap so that the temperature of the flue
gases does not drop bel
ow 90 ° C. In this case the throttle lever must be rotated downwards
(backwards) and secured by the locking bolt.
•
Optical sensor
(photodiode) detects the presence of the flame in the furnace. If there isn’t enough
flame in the furnace, the programmer starts automatic ignition, i.e. it will deliver a small amount of fuel to
the burner and the ignition spiral is activated. The ignition mode lasts for about 2 to 3 minutes and then
the boiler goes into normal operation mode. However, if the ignition does not occur, the whole process is
repeated (3 attempts in total). After an unsuccessful ignition a corresponding alarm appears on the
display of the programmer, and the burner will not work further until the fault is rectified.
•
Fuel feeder temperature sensor is located in the aerial chamber of the burner. In the event the fuel
burns through inside the screw feeder in the burner, the programmer interrupts the fuel supply from the
fuel store. This sensor is activated at the temperature of
60 ° C. This is a non-returnable alarm that can
only be removed by the user.
•
Fuel overflow is another safeguarding feature against the fuel burning through into the fuel store. This
is a design where both screw feeders (the feeder from the store and the feeder in the burner) are
connected by a fusible flexible hose and a connecting elbow. This creates an air gap in the fuel feed
path between the burner and the store which protects the fuel in the store against the ignition.