Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 37·3.2
Manufacturer's installation instructions for air vents
Where manufacturer's installation instructions require larger permanent air vent areas than Table 3.1 specifies, the manufacturer's requirements should be followed instead.
Where the manufacturer's installation instructions require greater areas of permanently open air vents than those specified in Table 3.1, the manufacturer's advice should be followed.
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