1、DIRECT GAS-FIREDCIRCULATING HEATERS FORAGRICULTURAL ANIMALCONFINEMENT BUILDINGSANSI/IASLC 2a-1998INTERNATIONALAPPROVAL SERVICESA Division of CSA8501 East Pleasant Valley Rd.Cleveland, Ohio 44131Addenda toANSI/IAS LC 2-1996PREFACEThe standards set forth herein apply to the first edition of the Standa
2、rdfor Direct Gas-Fired Circulating Heaters for Agricultural Animal ConfinementBuildings, ANSI/IAS LC 2-1996, and supersede corresponding standards therein.Following their preparation by the supervising subcommittee, they were acceptedby Accredited Standards Committee Z21/83 and subsequently approved
3、 as anAmerican National Standard by the American National Standards Institute, Inc.NOTE: Changes, other than editorial, are denoted by a vertical line in themargin.ApprovedNovember 16, 1998AMERICAN NATIONALSTANDARDS INSTITUTE, INC.Copyright 1998International Approval ServicesPermission is granted to
4、 republish material herein in laws orordinances, and in regulations, administrative orders, or similar documentsissued by public authorities. Those desiring permission for other republicationshould consult International Approval Services at the address noted above.Addenda toAMERICAN NATIONAL STANDAR
5、D FORCIRCULATING HEATERS FOR AGRICULTURALANIMAL CONFINEMENT BUILDINGSPART ICONSTRUCTION1.9 IGNITION MEANS (SYSTEMS)1.9.1 Automatic gas ignition systems (see Part IV, Definitions) and components shall comply with theapplicable construction provisions of the Standard for Automatic Gas Ignition Systems
6、 andComponents, ANSI Z21.20 or Combination Gas Controls for Gas Appliances,ANSI Z21.78iiCGA 6.20, or other nationally recognized standards covering such components.Automatic gas ignition system timings (see Part IV, Definitions) established under the above|standard shall not exceed those shown in Ta
7、ble II.|1.11 MANUAL GAS VALVES(Former 1.11.3, deleted.)(Former 1.11.4 becomes 1.11.3, unchanged.)1.14 AUTOMATIC VALVES AND SAFETY SHUTOFF VALVES1.14.1 A safety shutoff valve, unless provided as part of a combination gas control as specified in 1.10,shall be provided to shut off the main burner gas a
8、nd the pilot gas, if applicable. (See 1.9.3).|1.15 GAS PRESSURE REGULATORS1.15.2 A gas pressure regulator shall comply with the applicable provisions of the Standard for GasAppliance Pressure Regulators, ANSI Z21.18iiCGA 6.3, or the Standard for Combination GasControls for Gas Appliances, ANSI Z21.7
9、8iiCGA 6.20, as applicable.1PART IIPERFORMANCE2.1 GENERAL2.1.4 Heaters shall be tested in three modes: with full air flow, with the air inlet restricted and withthe air outlet restricted, unless otherwise specified. For the second and third modes, restriction|shall be imposed until any further closu
10、re would cause the heater to shut down within fifteenminutes.2.4 COMBUSTIONA heater shall not produce a concentration of carbon monoxide in excess of 25 ppm in a sample|of the flue gases, or if the sample obtained is over 25 ppm, 0.04 percent in an air-free sample of|the combustion gases when tested
11、 in an atmosphere having a normal oxygen supply.Method of TestCombustion gas samples should be taken at the air discharge outlet of the heater. Sample locationsshould be as defined in provisions 2.8.2-a and 2.8.2-b for the appropriate discharge configuration. Air-free calculations will be based on t
12、he average of the samples taken at these locations.a. The heater shall be operated in an atmosphere having approximately a normal oxygen supplyfor fifteen minutes at each of the operating conditions specified in Table XIII, at which timesamples of the combustion gases shall be secured and analyzed.b
13、. The gas supply pressure to a heater for use with LP-Gas shall be reduced to the minimum|pressure at which the heater will continue to operate for at least 15 minutes, at which timesamples of the combustion gases shall be secured and analyzed.c. On a heater provided with a power burner, an addition
14、al combustion sample shall be securedwith the heater operating at normal inlet test pressure and the supply voltage reduced to85 percent of the appliance rating plate voltage. The combustion sample shall be securedfollowing five minutes of operation at the reduced voltage.2.6 MANUAL AND PILOTED IGNI
15、TION SYSTEMS2.6.4 Under the conditions of voltage variation and pilot rate reduction specified in the followingMethod of Test, an automatic pilot ignition system shall ignite the pilot burner gas within30 seconds after gas reaches the pilot burner port(s).Method of TestBefore testing, it shall be de
16、termined that all gas piping is filled with gas. These tests shall beconducted at Test Conditions 1 and 3 in Table XIII under the following voltage and pilot input rateconditions:2a. UndervoltageThe voltage to the heater shall be adjusted to 85 percent of the appliance rating plate voltagewith the a
17、ppliance in operation.|b. OvervoltageThe voltage to the heater shall be adjusted to 110 percent of the appliance rating plate voltagewith the appliance in operation.|c. Reduced Pilot Input RateThe pilot gas supply shall be reduced to an amount just sufficient to keep the valve of thesafety shutoff d
18、evice open or to an amount just above the point of flame extinction, whicheverrepresents the higher pilot gas flow, and the appliance rating plate voltage shall be supplied tothe heater.Under the conditions specified in “-a,”“-b” and “-c” above, ignition cycles shall be repeated 10 times.In each cas
19、e the pilot igniter shall ignite the pilot burner gas within 30 seconds after gas reaches thepilot burner port(s).PART IVDEFINITIONSLOCKOUT TIME. The period of time between energizing the system and lockout if proof of the|supervised ignition source or the supervised main burner is not established.|
20、TRIAL FOR IGNITION PERIOD. The period of time between energizing and deenergizing the gas valve|if proof of the supervised flame is not established.|VALVE SEQUENCE PERIOD. The sum of all trial for ignition periods prior to lockout, if proof of the|supervised ignition source or the supervised main burner flame is not established.|3
