ORDINANCE NO. 8874 - Laserfiche WebLink

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434 - - - --- -- _s _ -- =-- - - _ - - = - -__ - - (f) No open flame or spark producing device shall be permitted in any refrigerating machinery room ~•fith a system containing a flammable refrigerant. 1 0 ~ (a) No system containing over 1,000 pounds of butane, ethane, propane or ether refrigerant having a flash point belo~~o 25° F. shall be permitted vaithin the folloTrring limits: Fire zones 1 and 2. (b) No system of the intermittent absorption type containing over 1,000 pounds of refrigerant shall be permitted, and no system of the intermittent absorpt- ion type containing over 100 pounds of refrigerant shall be permitted unless the heating medium is low pressure steam. (c) Coils carrying refrigerants which are flammable or which are toxic are defined in paragraph 1501 (c), shall not be placed in air ducts or other air cowling systems, Brine or water cooled by such refrigerants may be sprayed into such air passages or may be circulated through coils located in such passages, but no such brine shall contain any flammable constituent. 150li• (a) AlI refrigerant piping, tubing and fittings shall be of a material suit- able for the refrigerant employed. (b) Standard ~~all thickness pipe may be used tuhere a test pressure of 300 pounds extra heavy pipe shall be used. If flanged fittings are used they shall be of recessed gasket type. Piicing shall be rigidly secured in place. (c) Approved seamless metal tubing of cop~oer or other material suitable for the refrigerant may be used for refrigerant lines in systems containing not over 100 pounds of refrigerant. (d) Elevator, dumb~,raiter or other shafts containing moving objects shall not be used for cutlet or junction boxes, nor for tubing or piping carrying refriger- ant. - (e) Systems of more than 20 pounds capacity, or systems supplying two or more evaporators, :and using~•aeam3esa-metal-^tubing"for refrigprant-•lines, sha17. have all such tubing, exc®pt bet~~feen the coMpressor a.nd the nearest riser box or manifold, insta.l.led in iron pipe or other metal enclosure, frith suitable metal out7.et boxes for mai~ifords and for. all valves except these at the evaporators. Flexible metal enclosures may be used at bends or a.t terminals if not exceeding 6 feet in length a,nd rigidly fastened to connecting pipe and~or valve boxes. Each run of pipe shall be sealed or plugged at each junction box inlet trrith a, material not affected by moisture or the temperature of the line. A11 joir_ts sha,ll.be accessible and shall be of s~,Teated. t~~pes, except that flared joints may be used. for tubing not more than 5/6 inch in diameter and ~r~here the required test pressure does not exceed 1S0 pounds. Enclosures shah. be rigidly secured to the galls or other support. Tubing shall be independently supported. in such a manner as to prevent excessive vibration and strains at jointe and conneetiors. Valves, service cor_nections and joints in tubing s'rall be rigidly secured in suitable metal boxes at accessible points. 150 No system sha7.1 be placed in operation until the complete inst=.1?ation.has been tested by th? insta.ller in the presence of the authority enforcing this code. A certifics.~e of approval sr~a.l.l be posted on the premixes ~tiThere the system is installed. Tests shall include a vacuum test of the complete piping system,~preferably with the evaporators installed, but 'valves thereon may be closed to prevent trrithdrat~ral of th.e refrigerant; under this test a vacuum of 20 inches of mercury shall be placed upon the system and. shall be held for a period of, 20 minutes, ~f~ith no detectable - drop, after the pump has been stopped. After the vacuum test, the system of piping shall be tested by application of the pressure indicated in the table follo~ring: ~? _ . _ Test Pressures Righ Side Part Loaf Side Part Refrigerant Used Lbs. per,sq,. in. Lbs. per sq. in. Carbon dioxide ........................... 1,500 750 Amonia ................................... 300 150 g0 :Methyl Chlor.ide .......................... 1~0 50 Sulphur DioVide .......................... 13-5 ,. Iso-Butene ............................... 130 ' 50 Butane .................................... 7.5 35 Ethyl Cr~loride .....:..................... ,50 25 ... P~Iethylene Chloride........ ............ 15 0 15 30 uorotrichloromethane (F 11......... A§onof] 3 . Dichlorodif7.utc~romethane (F 12)........... 235 1~5 Trichlorotrifl~oroeth,-ne F 113•..••.•••••• 30 30 DichloromonofluoroMeth~ne (F21........... 70 30 Dichlorotetrafluoreeth~.ne (P` 11~......... 75 30