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the air blower and remove deposit that may accumulate on duct’s horizontal
connector.
3.5. Planned shutdown of the boiler
After the fuel burns out, open all doors and maximally open the damper in
the smoke conduit. Remove ash, clean the boiler. Do not drain the circulating
water. Cool down time is equal to the ignition time.
3.6. Emergency Shutdown of the Boiler
In case of emergency states, such as exceeded 100
O
C temperature,
installation elements breaks and loss of water charge, control & automatic
equipment or protection equipment failure or sudden pressure increase, it is
necessary to:
•
remove fuel from the grate and move outside the boiler room,
•
lower circulating water temperature by adding cold water to the
water charge, like during filling
•
maximally open the breeching throttle (if installed).
In case of boilers operating in closed systems, an emergency condition
may be any condition resulting from power outage (pumps stop) or from leaving
doors of the boiler open. The central-heating installation shall be protected with
a safety valve set to 2 bars, additionally the manufacturer shall protect the boiler
with safety valve, factory preset to 2.5 bar, however in case of an emergency
condition, such protections are insufficient. The boiler must be additionally
protected with a thermal protection valve, which will remove hot water from the
boiler in case of an emergency condition, while at the same time supplementing
thus caused shortage of water in the boiler with cold water from water pipe
installation in order to cool down the boiler and to reduce the pressure (section
2.6).
Keep in mind that emergency conditions are likely to occur during
summer, when only household hot water is heated in the boiler. To prepare for
such conditions, it is worth to consider installation of a heat accumulator capable
of taking over the heating power surplus unavoidable in such circumstances.
Glowing fuel must not be extinguished or cooled down with water.
