1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULAugust 30, 20111SUBJECT 724OUTLINE OF INVESTIGATIONFORINDIRECT FIRED, OIL BURNING COMMERCIAL COOKING APPLIANCESISSUE NO: 1August 30, 2011Summary of TopicsThis is the first issue of the Outline of
2、 Investigation for Indirect Fired, OilBurning Commercial Cooking Appliances, Subject 724. Theserequirements cover indirect fired oil-burning floor-supported food serviceequipment equipped with an oil burner providing coverage for griddles,baking and roasting ovens, deep fat fryers, and kettles, cons
3、tructedentirely of new, unused parts and materials for use in food service centersof commercial, industrial, institutional and public assembly buildings.COPYRIGHT 2011 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM
4、 ULAUGUST 30, 2011SUBJECT 7242No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTSINTRODUCTION1 Scope .62 Components 63 Units of Measurement .74 Undated References 75 Glossary .7CONSTRUCTION MECHANICAL6 Assembly .107 Se
5、rvicing 137.1 General 137.2 Moving parts 148 Base .159 Casings .1510 Radiation Shields .1511 Combustion Chambers 1612 Heating Surface Joints 1613 Baffles.1814 Flue Collars 1815 Dampers and Draft Regulators .1816 Air Intake Terminals .1917 Direct Vent (Vent-Air Intake Assemblies) 20CONSTRUCTION ELECT
6、RICAL18 Cord Connected Appliances 2118.1 Power supply cords .2118.2 Bushings 2118.3 Strain and push back relief 2219 Controls .2219.1 Application 2219.2 Limit control oil fired fryers .2319.3 Thermostats .2419.4 Liquid level controls 2520 Field Wiring 2520.1 General .2520.2 Leads and terminals 2621
7、Internal Wiring 2821.1 General .2821.2 Methods 2821.3 Short circuit protection 3122 Separation of Circuits .3223 Grounding .3324 Electrical Components .3725 Mounting of Electrical Components .3726 Electrical Enclosures 3826.1 General .3826.2 Electrical enclosure access panels and covers .47AUGUST 30
8、, 2011 SUBJECT 724 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL27 Motors and Motor Overload Protection 4927.1 General .4927.2 Motor overload protection .5128 Overcurrent Protection of High-Voltage Control-Circuit Conductors .5428.1 Genera
9、l .5428.2 Direct-connected high-voltage control circuit .5428.3 Tapped high-voltage control circuits 5428.4 Overcurrent-protective devices .5529 Overcurrent Protection of Transformers 5629.1 High-voltage transformers .5629.2 Low-voltage transformers 5730 Switches and Controllers 5731 Electrical Insu
10、lating Material 5832 Spacings - High-Voltage Circuit .5833 Spacings - Low-Voltage Circuits 59PERFORMANCE34 General 6035 Test Installation for Floor Mounting .6036 Instrumentation .6636.1 Flue draft 6636.2 Fuel input .6636.3 Power measurement 6636.4 Speed measurement .6636.5 Temperature measurement 6
11、737 Initial Test Conditions .6737.1 General .6738 Combustion Test .6839 Combustion Air Failure Test 6940 Burner Operating Characteristics .7041 Direct Acting Thermostat Calibration Tests .7041.1 Ovens 7041.2 Fryers 7141.3 Water Filled Cooking Appliances .7142 Limit Control Test Oil-Fired Fryers 7243
12、 Temperature Tests 7243.1 General .7244 Continuous Operation Test .7545 Fan Failure 7746 Door Relief .7747 Strain Relief and Push Back Relief Tests 7847.1 Strain relief 7847.2 Push back relief 7848 Ground Continuity Test 7849 Leakage Current Test Cord Connected Appliances Only .7950 Stability 7951 S
13、tructural Integrity Overall Appliance 8052 Structural Integrity - Food Supports, Shelves, Storage/Warming Areas 8053 Structural Integrity Drop Doors 8154 Structural Integrity Nonmetallic Covers, Guards, Panels, and Windows 8155 Transformer Burnout Test 8156 Short-Circuit Test 82AUGUST 30, 2011SUBJEC
14、T 7244UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL57 Dielectric Voltage-Withstand Test .8458 Direct Vent Appliance Tests 85MANUFACTURING AND PRODUCTION TESTS59 General 8560 Production Line Dielectric Voltage-Withstand Test 8661 Grounding C
15、ontinuity .88MARKING62 General 88INSTRUCTIONS63 Operating and Installation Instructions .92AUGUST 30, 2011 SUBJECT 724 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULINTRODUCTION1 Scope1.1 These requirements cover indirect fired oil-burning
16、floor-supported food service equipment equippedwith an oil burner providing coverage for griddles, baking and roasting ovens, deep fat fryers, and kettles,hereinafter referred to as “appliances,” constructed entirely of new, unused parts and materials for use infood service centers of commercial, in
17、dustrial, institutional and public assembly buildings.1.2 These requirements cover appliances intended to burn standard Grades No. 1 and 2 fuel oils asspecified in the Specification for Fuel Oils, ASTM D396, and standard Grades No. 1 and 2 diesel fuels asspecified in the Specification for Diesel Fue
18、l Oils, ASTM D975.1.3 Requirements for the installation and use of oil-burning equipment are included in the Standard forInstallation of Oil-Burning Equipment, NFPA 31, and in codes such as the BOCA National MechanicalCode, the SBCC Standard Mechanical Code, and the IAPMO Uniform Mechanical Code. Th
19、e applicablerequirements are to be utilized in conjunction with this outline.1.4 Appliances generating steam, at pressures above atmospheric, for cooking purposes are not coveredby these requirements.2 Components2.1 Except as indicated in 2.2, a component of a product covered by this standard shall
20、comply with therequirements for that component. See the individual sections of this Standard for componentrequirements.2.2 A component is not required to comply with a specific requirement that:a) Involves a feature or characteristic not required in the application of the component in theproduct cov
21、ered by this outline, orb) Is superseded by a requirement in this outline.2.3 A component shall be used in accordance with its rating established for the intended conditions ofuse.2.4 Specific components are incomplete in construction features or restricted in performance capabilities.Such component
22、s are intended for use only under limited conditions, such as certain temperatures notexceeding specified limits, and shall be used only under those specific conditions.AUGUST 30, 2011SUBJECT 7246UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM U
23、L3 Units of Measurement3.1 Values stated without parentheses are the requirement. Values in parentheses are explanatory orapproximate information.4 Undated References4.1 Any undated reference to a code or standard appearing in the requirements of this outline shall beinterpreted as referring to the
24、latest edition of that code or standard.5 Glossary5.1 For the purpose of this standard the following definitions apply.5.2 AIR SHUTTER An adjustable device for varying the size of the air inlet or inlets regulatingprimary and/or secondary air.5.3 APPLIANCE Refers to any equipment covered by these re
25、quirements unless specifically notedotherwise.5.4 APPLIANCE FLUE The flue passages within the appliance.5.5 AUTOMATICALLY LIGHTED APPLIANCE An appliance in which fuel to the main burner isturned on and ignited automatically.5.6 BASE The lowest supporting frame or structure of the appliance, exclusiv
26、e of legs.5.7 BODY The principal structure of the appliance, including the supporting frame, which givesstrength and rigidity to the appliance.5.8 BURNER BOX The surfaces immediately surrounding a burner.5.9 BURNER, MECHANICAL-ATOMIZING TYPE A power-operated burner that prepares anddelivers the oil
27、and all or part of the air by mechanical process in controllable quantities for combustion.Some examples are air and steam atomizing, high and low pressure atomizing, burners.5.10 CASING An enclosure forming the outside of the appliance, no parts of which are likely to besubjected to intense heat.5.
28、11 COMBUSTIBLE MATERIAL Combustible material as pertaining to materials adjacent to or incontact with heat-producing appliances, chimney connectors and vent connectors, refers to materialmade of or surfaced with wood, compressed paper, plant fibers, or other material that will ignite andburn. Such m
29、aterial shall be considered as combustible even though flameproofed, fire-retardanttreated, or plastered.5.12 COMBUSTION CHAMBER The portion of an appliance within which combustion occurs.5.13 CONTROL, LIMIT As it pertains to this standard, a safety control responsive to changes intemperature normal
30、ly set beyond the intended operating range of the appliance to limit its operation.5.14 CONTROL, PRIMARY SAFETY The automatic safety control intended to reduce the risk ofabnormal discharge of oil at the burner in case of ignition failure or flame failure.AUGUST 30, 2011 SUBJECT 724 7UL COPYRIGHTED
31、MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL5.15 CONTROL, SAFETY Automatic controls, including relays, switches, and other auxiliaryequipment used in conjunction therewith to form a safety control system, that are intended to reduce therisk of improper o
32、peration of the appliance.5.16 CONTROL, SAFETY COMBUSTION See Control, Primary Safety.5.17 COOKING VESSEL The liquid container in which the cooking process is conducted.5.18 DEEP FAT FRYER, FOOD SERVICE An appliance including a cooking vessel in which oils orfats are placed to such a depth that the
33、cooking food is essentially supported by displacement of thecooking fluid or a perforated container immersed in the cooking fluid rather than by the bottom of thevessel. For the purpose of this standard, a deep fat fryer shall be limited to a capacity of 300 lb or lessof cooking oil as determined by
34、 the manufacturers rating, and shall be designed primarily for use inhotels, restaurants, clubs and similar institutions.5.19 DRAFT REGULATOR, BAROMETRIC (AUTOMATIC DAMPER) A device that functions tomaintain a desired draft in the appliance by automatically reducing excess chimney draft to the desir
35、edvalue.5.20 ELECTRICAL CIRCUITS a) High-Voltage Circuit A circuit involving a potential of not more than 600 volts and havingcircuit characteristics in excess of those of a low-voltage circuit.b) Low-Voltage Circuit A circuit involving a potential of not more than 30 volts rms alternating-current (
36、42.4 volts peak) or direct current and supplied by:1) A Class 2 transformer, or by a battery, by a battery and fixed impedance, or by atransformer and fixed impedance each of which, as a unit is in compliance with what isrequired for a Class 2 transformer; or2) Is limited to a maximum of 100 volt-am
37、peres.A circuit derived from a source of supply classified as a high-voltage circuit, by connectingresistance in series with the supply circuit as a means of limiting the voltage and current, is notconsidered to be a low-voltage circuit.c) Isolated Limited Secondary Circuit - A circuit of limited en
38、ergy derived from an isolatedsecondary winding of a transformer having a maximum capacity of 100 volt-amperes and open-circuit secondary voltage rating not exceeding 1000 volts.d) Safety Control Circuit - A circuit involving one or more safety controls.5.21 ELECTRICAL ENCLOSURE The part of the appli
39、ance that surrounds insulated and uninsulatedcurrent-carrying live parts and that is intended to contain a fire resulting from an electrical fault.5.22 GRIDDLE An appliance having a cooking surface which transfers heat directly to a food productthrough convection or conduction.5.23 INDIRECT-FIRED AP
40、PLIANCE An appliance constructed so that combustion products or fluegases are not mixed in the appliance with the medium, that is, to be heated; hence is provided with aflue collar.AUGUST 30, 2011SUBJECT 7248UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMI
41、SSION FROM UL5.24 INDIRECT OVEN THERMOSTAT SYSTEM A control system of two or more integratedautomatic devices to maintain an oven temperature as selected by the operator. That portion of thesystem responsive to oven temperature causes operation of another portion of the system to turn on orshut off
42、the oil supply to the oven burner.5.25 INTENDED OPERATION Normal operation of the appliance where the fire, shock, andmechanical hazards are mitigated.5.26 KETTLE An appliance with a cooking chamber which is heated either by a steam jacket inwhich steam is generated by fuel heat or by direct fuel he
43、at applied to the cooking chamber.5.27 NON-COMBUSTIBLE MATERIAL Non-combustible material as pertaining to materials adjacentto or in contact with heat-producing appliances, chimney connectors and vent connectors, refers tomaterials that will not ignite and burn.5.28 NORMAL CARE The periodic tasks us
44、ually performed to operate and maintain an appliance,such as air, fuel, pressure, and temperature regulation, cleaning, lubrication, and resetting of controls.Repair and replacement of parts other than those expected to be renewed periodically is not consideredto be servicing. Some examples of servi
45、cing are:a) Cleaning or replacing nozzles, atomizers, and pilots.b) Setting ignition electrodes.c) Cleaning strainers or replacing strainer or filter element.d) Resetting safety control.e) Replacing igniter cable.5.29 OVEN, BAKING AND ROASTING An oven primarily intended for volume food preparationwh
46、ich can be composed of one or more sections or units of the following types:a) Cabinet Oven. An oven having one or more cavities heated by a single burner or group ofburners.b) Reel-Type Oven. An oven employing trays that are moved by mechanical means.c) Sectional Oven. An oven composed of one or mo
47、re independently heated cavities.5.30 OVEN, INDIRECT An enclosed compartment in which cooking is accomplished primarily byconvected heat in which the flue gases do not flow through the oven compartment.5.31 POSTPURGE PERIOD The period of time after the fuel delivered to the burner is stopped andduri
48、ng which the burner motor or fan continues to run to supply air to the combustion chamber.5.32 PREPURGE PERIOD The period of time during the burner start-up in which air is introducedinto the combustion chamber and the associated flue passages in such volume and manner as tocompletely replace the ai
49、r or fuel-air mixture contained therein prior to initiating ignition.5.33 PRIMARY AIR The air introduced into a burner and which mixes with the fuel before it reachesthe ignition zone.AUGUST 30, 2011 SUBJECT 724 9UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL5.34 READILY ACCESSIBLE Capable of being reached easily and quickly for operation, adjustment,and inspection.5.35 SAFETY SHUTDOWN (LOCKOUT) The shutting off of all fuel and ignition
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