andrews R18 Series, Technical Documentation Manual

Page: 28 / 71

18IP22B
20
Fig. 15 Ventilation an flue placements
Fig. 16 Extraction cap
5.1.3 Air supply and
ventilation
Natural ventilation
Where natural ventilation is required, permanent openings at
low and high level, communicating directly with the outside air,
shall be provided.
The openings shall be sited so that they cannot be easily block-
ed or flooded. The grilles shall have a total minimum free area
as follows, taking account of all fuel burning appliances.