UL 499
Standard for Electric Heating Appliances

DETAILS
Edition Number:14ANSI Approved: 2017-02-23
Edition Date:2014-11-07DOD Approved:1987-08-17
Price Code:BSCC Approved:--
Type:ulstd

  • SCOPE

    1 Scope

    1.1 These requirements cover heating appliances rated at 600 V or less for use in unclassified locations in accordance with the National Electrical Code (NEC), ANSI/NFPA 70.

    1.2 These requirements do not cover electric heating equipment or appliances that are covered by individual requirements that are separate from this Standard.

    1.3 For the purposes of this Standard, a heating appliance is defined as an electrically energized product that directly or indirectly generates heat to perform its intended function.

    1.4 These requirements also cover electrically energized products that generate steam for other than space heating purposes and have an electrical power rating of 15 kW or less per steam generating vessel.

    1.5 Except as noted for steam-bath generators, steam generating products of the type described in 1.4 having an electrical input power rating of more than 15 kW per steam generating vessel are to be evaluated by the requirements in the Standard for Heating, Water Supply, and Power Boilers – Electric, UL 834.

    1.6 Each steam generating vessel in a multi-vessel unit shall comply with these requirements. The unit shall also be provided with the marking in 53.42.

  • TABLE OF CONTENTS
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    • Cover
    • Transmittal
    • Table of Contents
      • Body
        • INTRODUCTION
          • 1 Scope
          • 2 Glossary
          • 3 Units of Measurement
          • 4 Undated References
        • CONSTRUCTION
          • 5 General
          • 6 Components
            • 6.1 General
            • 6.2 Requirements for Components
          • 7 Frame and Enclosure
          • 8 Assembly
          • 9 Stability
          • 10 Corrosion Protection
          • 11 Supply Connections – Permanently-Connected Products
            • 11.1 General
            • 11.2 Wiring terminals
          • 12 Supply Connections – Cord Connected Products
            • 12.1 General
            • 12.2 Strain relief
            • 12.3 Pin terminals
            • 12.4 Bushings
          • 13 Current-Carrying Parts
          • 14 Internal Wiring
            • 14.1 General
            • 14.2 Protection of wiring
            • 14.3 Splices
            • 14.4 Separation of circuits
          • 15 Heating Elements
          • 16 Electrical Insulation
          • 17 Thermal Insulation
          • 18 Motors
          • 19 Overcurrent Protection of Conductors and Heating Elements
          • 20 Motor-Running Overload Protection
          • 21 Motor and Power-Transformer Short-Circuit and Ground-Fault Protection
          • 22 General (Short-Circuit and Ground-Fault) Overcurrent Protection
          • 23 Thermal Cutoffs
          • 24 Lampholders
          • 25 Switches
          • 26 Automatic Controls and Control Circuits
          • 27 Spacings
            • 27.1 Line-voltage circuits
            • 27.2 Low-voltage circuits
          • 28 Grounding
          • 29 Leakage Current Collectors
          • 30 Pressure Vessels and Parts Subject to Pressure
          • 31 Protection Against Injury to Persons
        • PERFORMANCE
          • 32 General
          • 33 Power Input Test
          • 34 Leakage Current
          • 35 Escape Current Test
          • 36 Normal Temperature Test
            • 36.1 General
            • 36.2 Ceramics-baking kilns and ovens
            • 36.3 Charcoal ignitors
            • 36.4 Stock-tank de-icers, stock waterers, and the like
            • 36.5 Liquid heaters and vaporizers, cord-connected
            • 36.6 Poultry and livestock brooders
            • 36.7 Soldering irons and soldering guns and desoldering tools
            • 36.8 Solder pots, nonautomatic
            • 36.9 Warming trays
            • 36.10 Water heaters of the side-arm type
            • 36.11 Refrigerator defrosters
            • 36.12 Heat guns
            • 36.13 Hybrid adhesive guns
            • 36.14 Semi-rigid enclosed pet heating mat/pad
          • 37 Test of Insulation Resistance and Leakage Current as a Result of Moisture
          • 38 Dielectric Voltage-Withstand Test
          • 39 Mechanical Endurance Test
          • 40 Resistance to Impact
          • 41 Overflow Test
          • 42 Abnormal Operation Test
            • 42.1 General
            • 42.2 Products with breakable exterior surfaces
            • 42.3 Products with breakable surfaces
            • 42.4 Heat guns
            • 42.5 Ceramics-baking kilns and ovens
            • 42.6 Charcoal ignitors
            • 42.7 Stock-tank de-icers, stock waterers, and the like
            • 42.8 Warming trays
            • 42.9 Immersion heaters
            • 42.10 Liquid heaters
            • 42.11 Ovens
            • 42.12 Poultry and livestock brooders
            • 42.13 Solder pots, nonautomatic
            • 42.14 Soldering irons
            • 42.15 Hot plates
            • 42.16 Ceramic products
            • 42.17 Vaporizers of the resistance-wire type
            • 42.18 Heating appliances employing fans or blowers
            • 42.19 Hybrid adhesive guns
          • 43 Testing of Component Switches and Control Devices
            • 43.1 Overload test for motor switches
            • 43.2 Overload test for automatic controls
            • 43.3 Endurance test for thermostats
            • 43.4 Limited short circuit test for motor-control devices
          • 44 Strain Relief Test
          • 45 Push-Back Relief Test
          • 46 Test for Permanence of Cord Tag for Outdoor-Use Heating Appliances with Power-Supply Cords Less than 6 Feet (1.8 m)
          • 47 Crushing Resistance for Flexible Pet Heating Mats/Pads
          • 48 Appliance Coupler Retention
          • 49 Connector Current Interruption
        • MANUFACTURING AND PRODUCTION-LINE TESTS
          • 50 Production-Line Dielectric Voltage-Withstand Test
          • 51 Polarization and Grounding Continuity Tests
            • 51.1 Continuity of grounding connection test
            • 51.2 Polarization continuity test
            • 51.3 Electrical indicating device
        • RATINGS
          • 52 Details
        • MARKINGS
          • 53 Details
          • 54 Instructions
        • ELECTRODE-TYPE HEATING APPLIANCES
          • 55 Scope
          • 56 General
          • 57 Construction
          • 58 Operation Test
          • 59 Vaporizer-Operation Test
          • 60 Leakage Current Test
          • 61 Disassembly and Reassembly Test
          • 62 Markings
          • 63 Operating Instructions
          • 64 Label Adhesion Tests
        • THERMOSTAT OVERRIDE UNITS
          • 65 General
          • 66 Temperature Test
          • 67 Overload Tests
        • STEAM-BATH GENERATORS
          • 68 Scope
          • 69 General
          • 70 Construction
            • 70.1 Supply connection
            • 70.2 Temperature-limit controls
            • 70.3 Feed water solenoid valve
            • 70.4 Feed water sensors and circuits
            • 70.5 Low-water sensors and circuits
            • 70.6 Drain valve
            • 70.7 Pressure vessels and parts subject to pressure
            • 70.8 Pressure-relief device
            • 70.9 Protection against injury to persons
            • 70.10 Output pressure regulating valve
          • 71 Performance
            • 71.1 General
            • 71.2 Power input test
            • 71.3 Leakage current
            • 71.4 Test of insulation resistance and leakage current as a result of moisture
            • 71.5 Normal temperature test
            • 71.6 Abnormal operation – general
            • 71.7 Abnormal operation – no water
          • 72 Markings
          • 73 Instructions
            • 73.1 General
            • 73.2 Installation instructions
            • 73.3 Important safety instructions
        • METAL SHEATHED HEATING ELEMENTS COMPONENTS – GENERAL
          • 74 Scope
          • 75 General
          • 76 Glossary
        • METAL SHEATHED HEATING ELEMENTS COMPONENTS – CONSTRUCTION
          • 77 Construction
          • 78 Insulation
          • 79 Spacings
        • METAL SHEATHED HEATING ELEMENTS COMPONENTS – PERFORMANCE
          • 80 General
          • 81 Power Input Test
          • 82 Dielectric Voltage-Withstand Test
          • 83 Leakage Current Test
          • 84 Temperature Test
        • METAL SHEATHED HEATING ELEMENTS COMPONENTS – RATING
          • 85 Details
        • METAL SHEATHED HEATING ELEMENTS COMPONENTS – MARKING
          • 86 Details
        • DIRECT PLUG-IN HEATING APPLIANCES
          • 87 General
          • 88 Construction
          • 89 Performance
          • 90 Markings
        • APPLIANCES GENERATING ULTRAVIOLET (UV) RADIATION
          • 91 Appliances generating ultraviolet (UV) radiation
            • 91.1 General
            • 91.2 Construction
            • 91.3 Protection against injury to persons
            • 91.4 Performance
            • 91.5 Markings
            • 91.6 Instructions
        • ELECTRIC SOAP KETTLES
          • 92 Additional Requirements for Electric Soap Kettles
            • 92.1 General
            • 92.2 Construction
            • 92.3 Performance
            • 92.4 Markings and instructions
        • VIVARIUM HEATERS (REPTILE TANK HEATER) EMPLOYING THIN FILM RESISTANCE HEATING ELEMENTS
          • 93 Vivarium Heaters (Reptile Tank Heater) Employing Thin Film Resistance Heating Elements
            • 93.1 General
            • 93.2 Construction
            • 93.3 Performance
            • 93.4 Markings
            • 93.5 Instructions
    • Heat Guns Operating from Rechargeable Battery Power