5. Design guidelines | 6. Boiler start-up, operation...
5.G. Selecting the nominal heat output
of a boiler
The nominal boiler heat output must correspond to the heat
demand.
The heat demand for domestic hot water and central heating
systems is determined in accordance with the relevant
standards and regulations.
The process heat demand is calculated in accordance with
the relevant requirements of the production processes for
an individual plant. The nominal heat output of the boiler
must be selected by an authorised person based on thorough
calculations. Do not oversize the boiler
5.H. System venting
Water heating system venting must conform to the relevant
standards and regulations.
6. Boiler start-up, operation and stop
including emergency stop
6.A. Boiler inspection
Check the following before fi lling the boiler with water:
• boiler internal checks – clean and check the internal
insulation (fi re bricks);
• check movable parts, especially pressurised;
• check valves, especially safety valve;
• check controls, gauges, regulators (e.g. boiler control
system);
• boiler external checks – external insulation, boiler casing
etc.;
• check connected systems.
Remove any defects and faults in the boiler operation. Perform
a water test after major repairs, pressurised part replacement
and long downtimes.
Experts in heating
6.B. Filling boiler and system
System and boiler feed water must meet the design
requirement, see section 5.D. 'Water quality requirements'.
The difference between the feed water temperature and the
boiler shell temperature (ambient temperature) must be as low
as possible – a threshold difference of 30°C is recommended.
If this condition cannot be met, extend the boiler fi lling time.
Filling procedure:
• open feed valve;
• open return valve;
• open fi lling valve;
• check boiler and system condition and pressure device
integrity.
6.C. Start-up preparation
Check the following before boiler start-up:
• check if all the safety and fi re regulations and guidelines
in the quick guide to the safety and fi re regulations for
fuel systems and all components including ducts, valves,
controls, pumps etc. regarding gas tightness are followed;
• check system pressure – if the system pressure is too
low, increase the pressure (with a low fl ow rate to reduce
the volume of air introduced to the system);
• check fuel level in the storage hopper (refi ll if necessary
to allow installation of the storage hopper cover);
• check fuel level – check if the storage hopper is free from
foreign material (stones, steel parts etc.) which may affect
fuel conveying, burner operation or cause damage to feeder
components;
• check fl ue system – check if all fi re regulations are followed;
• check wiring system;
• check auxiliary equipment (e.g. swirl vanes, if installed);
• check boiler room ventilation system;
• check boiler condition (closed door side, cleanouts, pipe
stoppers, etc. and gas tightness).
User Manual Twin Bio - PLV 09.13
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