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4.3 FLUE TERMINAL POSITION
- The boiler MUST be installed so that the terminal is exposed to the external air.
- It is important that the position of the terminal allows free passage of air across it at all times.
- It is ESSENTIAL TO ENSURE, in practice that products of combustion discharging from the terminal can-
not re-enter the building, or any other adjacent building, through ventilators, windows, doors, other sources
of natural air infiltration, or forced ventilation/air conditioning.
- The minimum acceptable dimensions from the terminal to obstructions and ventilation openings are stated
in the table below.
- Where the lowest part of the terminal is fitted less that 2M (78 in) above ground, above a balcony or above
a flat roof to which people have access, the terminal MUST be protected by a purpose designed guard.
- In certain weather conditions the terminal may emit a plume of steam. This is normal but positions where
this would cause a nuisance should be avoided.
- After a period of use the terminal may become discoloured, this is normal.
Minimum dimensions of flue terminal positions
Terminal position
Minimum
clearances
Directly below an opening fixed vent windows,
etc.
Adjacent to an opening fixed vent windows, etc.
Below gutters.
Below eaves
From a vertical drain pipe or soil pipe
From an internal or external corner
Vertically from a terminal on the same wall
Horizontally from a terminal on the same wall
300mm
300mm
75mm
200mm
75mm
300mm
1500mm
300mm
