I. General
424.1 Scope. This article covers fixed electric equipment used for space heating. For the purpose of this article, heating equipment shall include heating cable, unit heaters, boilers, central systems, or other approved fixed electric space-heating equipment. This article shall not apply to process heating and room air conditioning.
424.2 Other Articles. Fixed electric space-heating equip- ment incorporating a hermetic refrigerant motor- compressor shall also comply with Article 440.
424.3 Branch Circuits.
(A) Branch-Circuit Requirements. Individual branch cir cuits shall be permitted to supply any size fixed electric space-heating equipment.
Branch circuits supplying two or more outlets for fixed electric space-heating equipment shall be rated
15, 20, 25, or 30 amperes. In nondwelling occupancies, fixed infrared heating equipment shall be permitted to be supplied from branch circuits rated not over 50 amperes.
(B) Branch-Circuit Sizing. Fixed electric space-heating equipment shall be considered continuous load.
424.6 Listed Equipment. Electric baseboard heaters, heating cables, duct heaters, and radiant heating systems shall be listed and labeled.
II. Installation
424.9 General. All fixed electric space-heating equipment shall be installed in an approved manner.
Permanently installed electric baseboard heaters equipped with factory-installed receptacle outlets, or outlets provided as a separate listed assembly, shall be permitted in lieu of a receptacle outlet(s) that is required by 210.50(B). Such receptacle outlets shall not be connected to the heater circuits.
FPN: Listed baseboard heaters include instructions that may not permit their installation below receptacle
outlets.
424.10 Special Permission. Fixed electric space-heating equipment and systems installed by methods other than covered by this article shall be permitted only by special permission.
424.11 Supply Conductors. Fixed electric space-heating equipment requiring supply conductors with over 60°C insulation shall be clearly and permanently marked. This marking shall be plainly visible after installation and shall be permitted to be adjacent to the field connection box.
424.12 Locations.
(A) Exposed to Physical Damage. Where subject to physical damage, fixed electric space-heating equipment shall be protected in an approved manner.
(B) Damp or Wet Locations. Heaters and related equip- ment installed in damp or wet locations shall be listed for such locations and shall be constructed and installed so that water or other liquids cannot enter or accumulate in or on wired sections, electrical components, or ductwork.
FPN No. 1: See 110.11 for equipment exposed to deterio- rating agents.
FPN No. 2: See 680.27(C) for pool deck areas.
424.13 Spacing from Combustible Materials. Fixed electric space-heating equipment shall be installed to pro
vide the required spacing between the equipment and adja
cent combustible material, unless it is listed to be installed
in direct contact with combustible material.