BS EN 1749:2020 pdf download
BS EN 1749:2020 pdf download.Classification of gas appliances according to the method of supplying combustion air and of evacuation of the combustion products (types).
Type B23, A type B2 appliance incorporating a fan upstream of the combustion chamber/heat exchanger.
Type B3. A type B appliance without a draught diverter, which is designed for connection via its concentric duct to a common duct system. This common duct system consists of a single natural draught flue. All pressurized parts of the appliance containing combustion products are completely enclosed by parts of the appliance supplying combustion air. Combustion air Is drawn into the appliance from the room by means of a concentric duct, which encloses the flue. The air enters through defined orifices situated In the surface of the duct.
Type B31. A natural draught type B3 appliance.
Appliances of this type are not foreseen.
Type B32. A type B3 appliance incorporating a fan downstream of the combustion chamber/heat exchanger.
Type B33. A type 83 appliance incorporating a Ian upstream of the combustion chamber/heat exchanger.
Type B4. A type B appliance, incorporating a draught diverter, that is designed for connection via its flue duct to its flue terminal.
Type 841. 3) A natural draught type 84 appliance.
Type 842. A type B4 appliance designed for a natural draught flue incorporating a fan downstream of the combustion chamber/heat exchanger and upstream of the draught diverter.
Type B43. A type 134 appliance designed for a natural draught flue incorporating a fan upstream of the combustion chamber/heat exchanger.
Type B. A type 134 appliance having an integral fan downstream of both the combustion chamber/heat exchanger and the draught diverter.
Type B. A type B appliance, without a draught diverter, that Is designed for connection via its flue duct to its flue terminal.
Type B51. 4) A natural draught type 85 appliance.
Type B52. A type B5 appliance incorporating a fan downstream of the combustion chamber/heat exchanger.
Type 853. A type B5 appliance incorporating a fan upstream of the combustion chamber/heat exchanger.
Type C41. A natural draught type C4 appliance.
Type C42, A type C4 appliance incorporating a fan downstream of the combustion chamber/heat exchanger.
Type C43. A type C4 appliance incorporating a fan upstream of the combustion chamber/heat exchanger.
Type C5. A type C appliance connected via its separate ducts to its separate terminals for the supply of combustion air and the evacuation of the combustion products. These ducts may terminate in zones of different pressure.
Type C51. A natural draught type C5 appliance.
Type C52. A type C5 appliance incorporating a fan downstream of the combustion chamber/heat exchanger.
Type C53. A type C5 appliance Incorporating a fan upstream of the combustion chamber/heat exchanger.
Type C6. A type C appliance which is intended to be connected to a separately approved and marketed system for the supply of combustion air and discharge of the combustion products.
Pictures for type C6 appliances have not been included. This is because such appliances are marketed without duct systems. When Installed such an appliance will have a configuration similar to one of the arrangements shown for other type C appliances, according to manufacturer’s Instructions. Appliance Technical Committees have the responsibility for inclusion of requirements and methods of test in their standards to ensure that type C6 appliances are suitable for their intended method of supplying combustion air and of evacuation of the combustion product.
Type C61. A natural draught type C6 appliance.
Type C62. A type C6 appliance incorporating a fan downstream of the combustion chamber/heat exchanger.
Type C63. A type C6 appliance Incorporating a fan upstream of the combustion chamber/heat exchanger.
Type C7. A type C appliance in which the combustion air supply and the combustion products evacuation is provided by its two vertical ducts. The combustion air is taken from a loft and the combustion products are discharged above the roof. A draught diverter is incorporated in the combustion products evacuation duct at a location above the combustion air inlet orifice(s)8).
Type C71 A natural draught type C7 appliance.
Type C72. A type C7 appliance Incorporating a fan downstream of the combustion chamber/heat exchanger,
Type C73. A type C7 appliance incorporating a fan upstream of the combustion chamber/heat exchanger.
