Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 68·5.3
Air supply to appliances
Permanently open air vents for oil burning appliances must provide free area as specified in Diagram 5.1, unless the manufacturer's installation instructions require a greater area.
The permanently open air vent for an oil burning appliance should have the free area as given in Diagram 5.1. However, if the manufacturer's installation instructions require a greater area of permanently open air vent then the manufacturer's advice should be followed.
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