(A) (1) Gas-fired floor furnaces shall be specifically approved by the Department for services in direct contact with combustible floors in which they may be installed.
(2) A separate manual shutoff valve shall be provided ahead of all controls and a union connection shall be provided downstream from this valve to permit removal of the controls of the floor furnace.
(3) Fixed ventilation by means of a duct or grille arranged to supply air from a permanently ventilated attic or underfloor space shall be provided to any confined space which encloses the floor furnace. The duct or grille shall be screened and have a free area at least twice the free area of the vent collar of the floor furnace or one square inch per 1,000 B.T.U. per hour of gas input, whichever is the greater, and shall be installed in such a manner as to ensure proper combustion.
(4) The following are requirements that will serve in properly placing the furnace or furnaces to serve one story.
(a) No floor furnace shall be installed in the floor or any aisle or passageway of any auditorium, public hall or place of assembly or in an exitway from any such room or space.
(b) With the exception of wall register models, a floor furnace shall not be placed closer than six inches to the nearest wall and wall-register models shall not be placed closer than six inches to a corner.
(c) The furnace shall be so placed that a door drapery or similar object cannot be nearer than 12 inches to any portion of the register of the furnace.
(5) Generally speaking, the more central the location, the better, favoring slightly the sides exposed to the prevailing winter winds. The floor around the furnace shall be braced and headed with a framework of material not lighter than the joists.
(B) Means shall be provided to support the furnace when the floor grille is removed.
(C) (1) The lowest portion of the floor furnace shall have at least a six-inch clearance from the general ground level except that where the lower six-inch portion of the floor furnace is sealed by the manufacturer to prevent entrance of water, the clearance may be reduced to not less than two inches.
(2) When these clearances are not present, the ground below and to the sides shall be excavated to form a “basin-like” pit under the lowest portion of the furnace. A 12-inch clearance shall be provided on all sides except the control side, which shall have an 18-inch clearance.
(D) Provision shall be made for an access door to the floor furnace by means of an opening in the foundation wall of at least 18 by 24 inches and a trap door of at least 24 inches by 24 inches, located at some convenient point and a clear and unobstructed passageway to the floor furnace of at least 18 inches high by 24 inches wide.
(E) Whenever the excavation exceeds 12 inches or water seepage is likely, a pit made of concrete, waterproof, not less than three and three fourths inches thick and extending four inches above grade level shall be used. The pit shall be not less than six feet by six feet inside dimension, with at least five and one-half foot clearance on the control side and clearance on all other sides not less than six inches.
(F) Floor furnaces shall be protected, where necessary against severe wind conditions.
(G) Listed gas floor furnaces may be installed in an upper floor provided the furnace assembly projects below into a utility room, closet, garage or similar nonhabitable space. In such installations, the floor furnace shall be enclosed completely (entirely separated from the nonhabitable space) with means for air intake to meet the provisions of this section, with access facilities for servicing on the control side, with minimum furnace clearance of six inches to all sides and bottom and with the enclosure constructed of Portland cement plaster on metal lath or material of equal fire resistance.
(H) (1) No gas-fired boilers, furnaces or other devices for space heating a building or buildings shall be installed and no boiler or furnace designed for other fuels shall be converted to the use of gas unless the following regulations are complied with.
(2) Either an automatic safety pilot, so constructed and adjusted that no gas can flow through the main burner unless the pilot is burning, or some other approved type of safety device serving this same end, shall be employed.
(3) Pilot burners shall be supported in such manner that their position relative to the main burner or shall be fixed.
(4) Pilot burner shall be so positioned as to be safely lighted and readily accessible for inspection, cleaning or replacement.
(5) Automatic safety pilots of gas burners having an hourly input of less than 400,000 B.T.U. shall be so adjusted that the main gas supply will be shut off within three minutes after the pilot flame has been extinguished.
(6) Gas burners having an hourly input of 400,000 B.T.U. or more shall be provided with a flame rod or other approved instantaneous type safety pilot which will shut off the main gas supply within ten seconds of pilot flame failure; except that safety pilot, which shuts off the main gas supply gas designed sectional cast iron boilers, will be accepted when provided with approved flame failure.
(7) Pilot flames shall be so adjusted as to effectively ignite the gas in the main burner or burners shall be adequately protected from drafts and shall not become extinguished when the main burner or burners are turned on or off in normal manner.
(8) All pilots shall be go adjusted as to prevent carbon deposits.
(9) All warm air furnaces shall be equipped with an approved high temperature limit device and set not to exceed 200°F for mechanical air distribution. All hot water boilers shall be equipped with an approved high water temperature limiting device and the boilers shall be equipped with approved pressure limiting devices and approved low-water and steam boilers shall be set so as not to exceed the limitations as specified by the regulations of the American Society of Engineers. These limiting devices shall be in addition to operating controls.
(I) (1) An approved gas pressure regulator of sufficient size shall be installed in the gas line leading to the gas burner. An additional approved adjustable gas pressure regulator shall be installed in the gas pilot supply line.
(2) All gas pressure regulators or diaphram control valves, used with the space heating equipment shall be vented to a constant burning pilot so that any gas leaking to the atmospheric side of the regulator or control valves will be carried to and ignited by the pilot or an approved venting device shall be used.
(3) On burners where no constant burning pilot is provided, the gas pressure regulator or diaphragm control valve shall be vented to the smoke pipe on the chimney side of the draft diverter or directly to the outside atmosphere.
(J) (1) An approved manual main shutoff valve shall be provided ahead of all control and a union connection shall be provided downstream from this valve to permit, removal of the controls or equipment.
(2) A pilot supply line shall be installed on the supply side of an approved main burner shutoff device through an approved fitting and shall be equipped with a shutoff valve and an adjustable pilot gas pressure regulator.
(3) Drilling and tapping the fuel line for the purpose of connecting a pilot gas supply line is prohibited.
(K) (1) All gas burners shall consist of factory assembled and tested units.
(2) Gas burner units shall be so installed or attached as to prevent twisting, sliding or dropping out of the intended correct position.
(3) Burners shall be so installed as to be readily accessible for inspection and cleaning and no part of the flames shall impinge so as to cause incomplete combustion. No baffles shall be applied which will interfere with proper combustion.
(4) Air shutters shall be adjusted to produce a good flame at the prevailing gas pressure.
(5) Secondary air openings shall provide sufficient area to supply an adequate amount of air for complete combustion and, if automatically controlled, the construction shall be such that, in case the control fails in any way, either the gas will be shut off or the secondary air door will remain open.
(6) The flames from constant burning pilots and burners shall freely ignite the gas from adjacent burners when operating at prevailing gas pressure and when the main control valve is regulated to deliver about one-third the full gas rate.
(7) Burners shall not expel gas through air openings in mixer faces when operating at prevailing pressures.
(L) The combustion chamber, and all of its passages, shall be gastight.
(M) The fuel door of a converted appliance shall be arranged to relieve pressure due to puffs or backfire caused by delayed ignition or other causes and shall be provided with an approved self-closing device.
(N) Every gas-fired boiler, furnace or other space heating device shall be effectively vented to the outside atmosphere.
(O) Where dampers are an integral part of the equipment, they shall be removed or permanently secured in the wide-open position, except such dampers as may be used to alter the passage of flue passes through the equipment, which will be located in such a position as not to interfere with the safe operation of the burner.
(P) (1) Every gas-fired boiler, furnace or other non-portable space heating device shall be connected to a flue.
(2) In case of conversion burners, the section of the vent pipe between the outlet of the equipment and the chimney shall be full size as the flue collar of the appliance and in no case less than one square inch per 6,500 B.T.U. hourly input. Where the outlet from the equipment is larger than the above indicated size, an orifice plate or other approved restricted section may be inserted.
(3) No adjustable dampers in the flue pipe shall be permitted.
(4) A draft hood or diverter of approved design or its approved equivalent shall be placed in and made a part of the flue pipe from the equipment or in the equipment itself. Such device shall be designed to ensure the ready escape of the products of combustion in the event of no draft, back draft or stoppage beyond the equipment, prevent a back draft from entering the equipment and neutralize the effect of stack action of the flue on the operation of the burner and shall otherwise comply with the requirements hereinafter specified for such devices and their installation.
(5) The draft hood or diverter shall be located at a point not lower than the top of the highest flue passage.
(Q) The draft hood or diverter shall be located at least one foot higher than the top of the highest flue passage for equipment of the revertible(down draft furnace) flue type and all boilers or furnaces of this type not specifically designed for the use of gas fuel shall be so altered or equipped as to prevent accumulation of gas in any part thereof.
(Ord. 19, passed 1-7-1955)