2.3.4 Ventilation requirement for boiler room
Introduction
The external combustion air must meet certain requirements to ensure that adequate
combustion air is supplied to the boiler and no by-products from the combustion get
into the boiler room.
Ventilation air for the boiler room must be taken from and expelled directly outside,
and the openings and air ducts must be designed to prevent weather conditions (e.g.
from foliage or snowdrifts), plants or animals from obstructing the air flow. Permanent
ventilation is required to ensure that the boiler runs smoothly.
In North America there are several regulations which govern the minimum require‐
ments of combustion air for chimneys.
The boiler must be installed in such a way that it receives adequate ventilation and
combustion air and that the fuel in the boiler burns. The exhaust air must be expelled
safely outside via the chimney and maintained within a safe temperature range.
Boiler rooms are usually so small that normal ventilation does not provide enough air
and air must be brought in from outside. External air openings and air channels must
be of an appropriate size to supply adequate combustion air. The design must comply
with NFPA 211.
Consult your local chimney inspector for the installation and install the boiler in accord‐
ance with the applicable local regulations.
Recommended size of air openings according to NFPA 54 and NFPA 211:
The boiler requires a fresh air supply of between 1 sq.in. per 2,500 BTU/h and
1 sq.in. per 4,000 BTU/h (550 mm²/kW and 880 mm²/kW), depending on local condi‐
tions and the climate zone. Local conditions may necessitate an additional air supply.
2.3.5 Requirements for the heating system
▪ The whole heating system must be designed in accordance with relevant national
and local regulations.
▪ The boiler’s nominal load must be adjusted to the calculated heating requirements
of all the consumer loads connected in the heating circuit in summer and winter.
▪ The heating system must be big enough to transport the heat generated by the
boiler and an additional heat source (if present). The pressure throughout the
whole system including all heating zones must be even.
▪ Special equipment must be available for filling and ventilating the heating circuit.
Flow valves and zone valves must be fitted to set the correct water flow volume.
▪ All fitted pipes must be water-tight and air-tight and safely insulated.
▪ If there is a risk of parts of the heating system freezing, add anti-freeze to the wa‐
ter in these heat zones.
2.3.6 Requirements for the boiler room
▪ There must not be a potentially explosive atmosphere in the boiler room as the
boiler is not suitable for use in potentially explosive environments!
▪ The boiler room must be frost-free.
Safety
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Requirements at the place of installation
Owner´s Manual S3 Turbo | B1390016_en-us
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