(a) General considerations.
(1) All equipment and apparatuses, in addition to complying with the requirements of the department, must also meet the requirements of other agencies, such as the New York City Board of Standards and Appeals, the Fire Department of New York, and the New York City Department of Buildings. Compliance with any requirements of either New York State or federal rules and regulations that may be instituted and not covered here is required. In the absence of any regulatory provisions, consideration must be given to recommendations published in the standards of nationally recognized organizations. These organizations include the American National Standards Institute, the American Society of Heating, Refrigerating and Air Conditioning Engineers, the American Society of Mechanical Engineers, the American Gas Institute, Underwriters' Laboratories, and the National Fire Protection Association, and the recommendations of equipment or apparatus manufacturers.
(2) The design engineer must estimate the heat demand before selecting a boiler or boilers. When application is made for an installation for a new structure or for a replacement boiler (when the boiler maximum heat input rating size is increased by more than 20 percent from the previously filed application of record), the analysis and calculations for estimating the heat demand must be submitted in a form acceptable to the department. This must be done in accordance with the procedures prescribed by the 2009 ASHRAE Fundamentals Handbook, or as required for the New York City Energy Conservation Code, as codified in Chapter 10 of Title 28 of the New York City Administrative Code, and as accepted by the department.
(3) For dual-fuel installations using #6 or #4 fuel oil as a back-up fuel for natural gas, design requirements set forth by the department must be followed. However, these installations must still meet the #2 fuel oil emission standards and must be held to the most recent performance requirements.
(b) Fuel burners.
(1) An oil burner must be capable of atomizing the oil by properly mixing it with adequate combustion air. A gas-fired burner must be capable of mixing the gas with adequate combustion air.
(2) A new burner must be listed by UL, CSA Group, ETL, or any other national recognized testing laboratory that uses UL testing conditions and have their Listing Mark label.
(3) A new burner, except for atmospheric equipment, must have, integral with it, a fan which is capable of supplying all combustion air.
(4) A burner must be sized such that, when fired with a boiler, the fuel delivery rate is within 80 percent and 110 percent of the maximum heat input rating of the boiler.
(c) Fresh Air Requirements.
(1) Provision must be made to provide a sufficient amount of air for proper combustion (to the oil-or natural gas-burning equipment room) and, in addition, a sufficient amount of bypass air necessary for the proper operation of a barometric damper when used. In addition, sufficient air must be provided to adequately ventilate the room and maintain the ambient temperature at safe and comfortable limits under normal conditions of use. In all cases a separate ventilation system must be provided independent of any other ventilation system.
(i) Mechanical ventilation must be designed such that 226 cfm @ 94F is provided for each million Btu per hour for up to 30 percent excess combustion air. Larger fan capacities would be needed for installations operating with greater than 30 percent excess combustion air. In all cases, where the combustion air is not ducted directly from the outside to the burner air intake, the room in which the burning equipment is located must be maintained at a pressure not less than outside atmospheric pressure. Exhaust fans are acceptable for ventilation provided the net ventilation is greater than or equal to the amount required for combustion.
(ii) When mechanical ventilation is not utilized, the minimum requirement for combustion air entrance must be a louvered opening in a wall to the outside air. The louvered opening must have a net free area of 86 square inches for every one million Btu per hour (based on the maximum heat input rating) and must never be less than the average internal cross-sectional area of the chimney. In addition, the net free area of the louver must be increased in size equivalent to the opening of a barometric damper or dampers, when provided, for bypass air. When necessary, a metal grate over a vault below the sidewalk may be permitted as long as the net free area requirement is met and suitable drainage facilities are provided. The net free area when the actual louver efficiency is unknown must be based on a maximum efficiency of 60 percent for both motorized and fixed metal single vane louvers and 50 percent for fixed metal double vane louvers. Where the efficiency of the louver can be demonstrated by the manufacturer to be greater than the above, the greater value may be used. The area of the louver is to be based on the inside frame dimensions and not the outside or nominal dimensions. The louver must be so constructed or suitably located or protected (i.e., cinder blocks, metal bars) so that it cannot be crushed or deformed since this would diminish the free area. Furthermore, any reduction of free area due to protective devices must be considered. Screening over louvers, if provided, must be not smaller than 1/4 inch mesh and must be readily accessible for cleaning.
(iii) When ducts are required to provide fresh air, they must meet the same minimum requirement for cross-sectional area as specified in subparagraph (ii) above. Note that a louver is not required where ducts are utilized to provide ventilation, although, consideration should be given to protective devices and any diminution of free area resulting from same. Access ports must be provided for the purpose of cleaning and observing conditions within the duct(s). All access ports must be ample size, but not less than 8 × 8 inches. A tight metal fitting cover must be provided for each port. All ports must be closed when not in use.
(A) Access ports for cleanout must be located to allow accessibility to all duct sections and must be placed at intervals to allow for safe and reasonable access to all sections of the breeching for the purposes of cleaning. The number of clean-outs must be determined by the configuration of the duct lay-out. Every duct must be provided with at least one access port for cleanout.
(B) Access ports for observation purposes must be provided within one diameter of all internal dampers.
(C) One access port may be used to serve both functions if suitably located.
(iv) Motorized louvers or motorized dampers in ducts must be provided, on installations where the maximum heat input rate of the boiler(s) is 7.0 million Btu per hour or greater which must close off the admission of combustion air during burner-off periods.
(2) Breeching must be installed so as to vent the combustion gases from the boiler to the chimney.
(i) Access ports must be provided for the purpose of cleaning and observing conditions within the breeching. All access ports must be of ample size but not less than 8 × 8 inches. A tight fitting metal cover must be provided for each port. All ports must be closed when not in use.
(A) Access ports for the cleanout of oil burning installations must be located to allow accessibility to all breeching sections and must be placed at intervals to allow for safe and reasonable access to all sections of the breeching for the purposes of cleaning. The number of clean-outs must be determined by the configuration of the breeching lay-out. Every breeching must be provided with at least one access port for cleanout.
(B) For short breeching runs (less than 15 feet in total), the barometric damper may be used as the clean-out port.
(C) Access ports for observation purposes must be provided within one diameter of all internal motorized damper locations.
(D) One access port may be used to serve both functions if suitably located.
(ii) The following should be considered when designing a new breeching:
(A) The equivalent inside diameter should normally be no smaller than the outlet of the boiler and should be sized on the basis of maintaining a flue gas velocity not greater than 30 feet per second.
(B) Breechings should be as short and straight as possible to prevent unnecessary draft losses (which may necessitate larger chimneys, induced draft fans, etc.).
(C) Breechings should be constructed so that changes in direction, shape and cross-sectional area are accomplished separately. All such changes should be accomplished as gradually as possible to eliminate turbulence with consequent adverse effects on available draft. If the width of breeching is greater than the inside width of the chimney, a contoured transition piece should be installed. The transition section should maintain the area of the breeching while altering its configuration so as not to exceed the chimney width.
(D) The breeching connection to the chimney should be such that it ends flush with the inside surface of the chimney.
(3) Chimneys must be designed and installed so as to vent the products of combustion to the atmosphere while at the same time avoiding a potential or actual nuisance. Chimneys must not be fitted with raincaps or covers of any kind.
(i) New chimneys or reconstructed chimneys must be of tight construction and must be provided with a cleanout chamber at the base. The chamber must have a horizontal cross-sectional area equal to that of the chimney and must be equipped with a tightly fitted metal door of ample size but not less than 8 × 8 inches. The bottom of the breeching must be located at least one chimney diameter above the base of the cleanout chamber. Factory-made chimneys and special gas vents must be installed per the manufacturer's specifications.
(d) Control devices.
(1) A boiler must be provided with acceptable control device(s) so as to maintain the desired boiler output under all normal operating conditions to meet the minimum performance requirements described in 15 RCNY § 2-08.
(2) A burner must be provided with acceptable control device(s) so as to maintain the desired fuel-air ratio under all normal operating conditions to assure complete and smokeless combustion.
(3) The burner control system must be permanently interlocked, unless the system is continuously staffed and supervised, with all ventilation fans, motorized louvers and dampers to prevent operation of the burner without the proper operation of the fan, louver, or damper. This must be accomplished with an air switch, or other approved means, to assure that the fan is operating or that the louver/damper has opened before the main fuel valve opens. This requirement does not prohibit operating fans and opening louvers or dampers for ventilation purposes during periods when the burner(s) are not in operation, although continuous, uninterrupted operation of the fan, independent of the burner, must not be permitted except for existing central ventilation systems.
(4) Provision must be made, concerning the burner fan, to cause minimum pre-purge and post-purge periods as recommended by the burner manufacturer to prevent accumulation of unburned oil.
(e) Draft Regulators.
(1) All installations must be designed such that an adequate draft can be maintained to provide sufficient combustion air and remove the products of combustion under normal conditions of use or when the outside temperature varies between 11°F and 94°F.
(2) Power operated draft regulators must be of an acceptable type designed to maintain a safe damper opening at all times and arranged to prevent starting of the burner unless the damper is opened to a safe position. The damper must be sized so that it comprises the full cross-sectional area of the breeching with appropriate allowances for clearance. Upon shut-down of the burner the damper must go to a safe closed position. The axis-rod (i.e., control rod) about which the damper rotates must have a square cross section or if round, must be welded to the control arm. An arrow must be provided on the axis-rod to indicate the position of the damper.
(3) Draft sensing lines must be a minimum of 1 1/4 inch pipe size, installed through the furnace wall, provided with a full size cleanout plug, and must otherwise conform to the equipment manufacturer's specifications. Details concerning the length and diameter of the draft sensing lines must be shown on the plans or specified in the plan notes.
(4) Barometric dampers must be of an acceptable type designed so as to provide a constant draft at a point directly upstream of the barometric damper under all normal operating conditions or when the outside temperature varies between 11°F and 94°F. However, in no case under steady state conditions must a pressure exist in the breeching at the barometric damper which is greater than the boiler room pressure. The minimum cross-sectional opening of the barometric damper must be at least as large as the diameter or equivalent diameter of the breeching to which it is connected.
(5) A draft control must not be required where an acceptable boiler assembly is designed and installed according to the manufacturer's requirements, and a positive pressure exists at a location in the chimney within three diameters of the chimney outlet.
(6) A boiler must be provided with acceptable control device(s) so as to maintain adequate draft (positive or negative as required) necessary for proper gas flow both to supply sufficient combustion air and exhaust combustion gases under all normal load and atmospheric conditions.
(i) A separate draft control must be provided for each boiler and be of the same type and must be installed per the manufacturer's specifications.
(ii) Draft control must be accomplished by a power operated draft regulator with low-draft cut-off. A barometric damper may be substituted for a power operated draft regulator if
(A) an on-off or low-high-off with low-fire start combustion controller is used or
(B) a forced draft burner is used.
(7) Oil-fired equipment, including dual-fuel installations, must be provided with a smoke alarm and combustion shutoff. This equipment must conform to the following specifications as well as applicable sections of the Air Pollution Control Code: The requirements of the above paragraph must not apply to a temperature controlled dual-fuel system (as set forth below) when the maximum heat input rate is less than 4.2 million Btu per hour. A temperature controlled dual-fuel system must comprise a fuel burning installation capable of burning natural gas and #2 fuel oil. The system must be designed and must operate such that the fuel burned will normally be gas except that when the outdoor temperature drops below 20°F, the equipment will automatically switch to #2 fuel oil and when the outdoor temperature rises above 25°F, the equipment will automatically return to natural gas operation.
(i) The smoke alarm must be regulated for both brightness intensity of the light source and sensitivity of the detector. It is recommended that the light source have a relatively uniform intensity over a reasonably long life.
(ii) The smoke alarm must cause both an audible (loud enough to be heard 20 feet from the source) and readily visible (a flashing red light) signal upon the emission of an air contaminant of an opacity of 20 percent or greater.
(iii) The smoke alarm must activate an additional signaling device located at the principal work location of the person supervising the equipment. If there is no principal work location, the additional signaling device must be located at an acceptable alternate location outside the boiler room.
(iv) The smoke alarm must cause the signaling devices to be activated in the event that the light source in a photoelectric type detector fails to operate properly. The signals must continue until the unit is manually reset.
(v) The smoke alarm must be provided with a suitable metal grid or equivalent, which meets the manufacturer's recommendations, calibrated so that when placed in the light path of the detector it will cause a response equivalent to an air contaminant as described in subparagraph (ii) above. This calibration must be indicated on the grid holder or frame. This grid must be securely fastened by means of a welded link chain of suitable length to the body of the detector. Provision must be made to temporarily hang the grid in front of the sensing element of the detector to facilitate proper adjustment of the light source and calibration of the instrument.
(vi) The installation of the smoke alarm must be such that
(A) it is wired to function at all times and
(B) it includes means necessary for sealing the breeching to prevent blowout of combustion products when necessary.
(vii) If two or more units of equipment are connected to a single flue, one air contaminant detector may be used if installed to monitor all of the units. This arrangement, however, will result in the shut-down of all units of equipment upon activation of the combustion shutoff.
(viii) The combustion shutoff automatically halt the operation of equipment within two minutes of continuous emission of an air contaminant of a density which appears as dark or darker than 20 percent opacity, unless the system is continuously staffed and supervised. The combustion shutoff must be designed such that once it has been activated, the equipment cannot resume normal operation without manual reset.
(Amended City Record 3/15/2017, eff. 4/14/2017)