Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 41·3.12
Flue outlet position in common circumstances
Flue outlet positions should comply with Table 3.3, though positions and separations may need to be increased in cases where wind exposure, surrounding buildings, trees, or high ground adversely affect flue draught.
The flue outlet position, in common circumstances, should be in accordance with Table 3.3. However, the flue outlet position and/or separations shown in Table 3.3 may have to be increased, in particular cases, where the wind exposure, surrounding tall buildings, high trees or high ground have an adverse effect on the flue draught.
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