4
11
4.3 - InstallatIon - flue regulatIons
ventilation and Combustion air
Conventional flue Boilers
an adequate supply of combustion and ventilation air is essential for efficient and safe boiler
operation and the openings for this should be positioned to cause least possible draught, with no
possibility of being accidentally blocked.
Please note: The British Standard Code of Practice for Oil Firing BS 5410 Part 1: 2014, requires a
permanent air inlet opening of 55mm
2
per kW of boiler rated output. (Note: 1kW = 3412 BTU/h).
also, when the boiler is installed in a compartment or confined space, ventilation openings are
required to ventilate and to avoid overheating in the boiler area.
OPEN FLUE
BOILER IN ROOM
BOILER COMPARTMENT
VENTILATED FROM OUTSIDE
BOILER COMPARTMENT
VENTILATED FROM ADJOINING ROOM
55mm
2
/kW
55mm
2
/kW
55mm
2
/kW
110mm
2
/kW
110mm
2
/kW
165mm
2
/kW
Combustion & ventilation air supply for conventional open flue boilers
The figures shown are free areas of grilles in mm
2
per kW of appliance rating (output).
FULL TeXT of both BS 5410 Part 1: 2014 and appropriate Building
Regulations for each country should be obtained and fully applied.
n.B. Please note:
BS5410-1: 2014 only permits room sealed models to be installed in a garage.
definitions
Combustion air: air required directly by boiler oil burner for combustion process.
ventilation air : air required in room for ventilation, cooling, etc. and to promote
a healthy living environment.
