J GENERAL GUIDANCE O N L I N E V E R S I O N J 37. The rated heat output for a solid fuel appliance is the manufacturer’s declared nominal energy output rate (kW) for the appliance. This may be different for different fuels. 38. A room-sealed appliance means an appliance whose combustion system is sealed from the room in which the appliance is located and which obtains air for combustion from a ventilated uninhabited space within the building or directly from the open air outside the building and which vents the products of combustion directly to open air outside the building (see Diagram 4 (b), (d) and (f)). 39.
Solid biofuel means, for the purpose of this Approved Document, a solid fuel derived from plants and trees. It can include logs, wood chips, wood pellets and other processed plant material. 40. A throat is a contracted part of the flue between a fireplace recess and its chimney (see Diagram 22). Throats are usually formed from prefabricated components as shown in Diagram 29. Measuring the size of flues and ducts 0.5 The size a flue or duct (area, diameter etc) should be measured at right angles to the direction in which gases flow. Where offset components are used, they should not reduce the flue area to less than the minimum required for the combustion appliance (see Diagram 7).
Diagram 7 Measurement of flues and ducts 16 Combustion appliances and fuel storage systems Approved Document J O N L I N E V E R S I O N