1. Scope1.1This Standard applies to central warm air electric resistance type furnaces which are either incorporated in a solid fuel fired furnace or are attached to a solid fuel fired furnace, so as to form a single unit which can be used as an electric furnace, a solid fuel fired furnace, or both simultaneously if so designed.1.2This Standard applies to electric furnaces in combination with solid fuel fired furnaces which are designed for residential use at not more than 150 V to ground and are intended for installation in accordance with the Canadian Electrical Code, Part I.1.3This Standard does not apply to electric furnaces which are installed as field ""add-ons"" or to add-on electric plenum heaters which are covered by CSA Electrical Bulletin No. 1302.1.4This Standard does not apply where the combination unit is used in conjunction with or is intended to be added to an oil fired or any other heat energy source of a comfort heating appliance.