Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 24·2.12
Permanently open ventilation of rooms
Rooms containing open-flued appliances must receive continuous outside air supply through permanently open vents, with the volume depending on appliance type and rating.
A room containing an open-flued appliance must receive a continuous supply of air from outside. The volume of air required depends on the type and rating of the appliance. This normally means the installation of permanently open air vents into that room.
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