EN 437 pdf free download
EN 437 pdf free download. Test gases – Test pressures – Appliance categories.
6 Classification of appliances 6.1 Appliance categories 6.1.1 General Appliances are classified into categories defined according to the gases and the pressures for which they are designed. The definition of the categories follows from 6.1.2, 6.1.3 and 6.1.4. In each country, taking account of the local gas distribution conditions (gas composition and supply pressures), only some of the categories defined in 6.1.2, 6.1.3 and 6.1.4 are marketed. In addition, some of these categories are used only for certain types of appliance as specified in the individual standards. The conditions concerning the marketing of these appliance categories in each country and the corresponding supply pressures are given in Tables B.1, B.2 and B.3 (see also B.4 for the categories marketed locally and nationally, corresponding to the gases and specific supply pressures given in Table B.5; B.6 gives the particular conditions specific to certain countries). NOTE See also annex C: Guidelines for extension to other categories. 6.1.2 Category I Appliances of category I are designed exclusively for the use of gases of a single family or of a single group. 6.1.2.1 Appliances designed for use on first family gases only Category I 1a : appliances using only gases of group a of the first family at the prescribed supply pressure (this category is not used). 6.1.2.2 Appliances designed for use on second family gases only Category I 2H : appliance using only gases of group H of the second family at the prescribed supply pressure. Category I 2L : appliances using only gases of group L of the second family at the prescribed supply pressure. Category I 2E : appliances using only gases of group E of the second family at the prescribed supply pressure. Category I 2E+ : appliances using only gases of group E of the second family, and operating with a pressure couple without adjustment on the appliance. The appliance gas pressure regulating device, if it exists, is not operative at pressures in between the two normal pressures of the pressure couple. Category I 2N : appliances using only second family gases at the prescribed supply pressure and that automatically adapt to all gases of the second family. Category I 2R : appliances having a pressure governor using all the gases of the second family and/or gases linked to the second family which can be adjusted manually in order to utilize the various gases of a group of the second family under the local condition of distribution (see Table B.6). 6.1.2.3 Appliances designed for use on 3 rd family gases only Category I 3B/P : appliances capable of using the third family gases (propane and butane) at the prescribed supply pressure. Category I 3+ : appliances capable of using gases of the third family (propane and butane) and operating with a pressure couple without adjustment of the appliance. However, for certain types of appliance specified in the particular standards, adjustment of the primary combustion air may be permitted when changing from propane to butane and vice versa. No gas pressure regulating device is permitted on the appliance. Category I 3P : appliances using only gases of group P of the third family (propane) at the prescribed supply pressure. Category I 3B : appliances using only gases of group B of the third family (butane) at the prescribed supply pressure. Category I 3R: appliances having a pressure governor using all the gases of the third family which can be adjusted manually in order to utilize the various gases of a group of the third family under the local condition of distribution (see Table B.7).EN 437 pdf download.
