Gas burners and devices, attachments or accessories
to gas burners, which can in any way affect combustion or safety,
shall not be installed until they have been inspected, tested and
approved by the Inspector.
A. This inspection and test shall cover arrangement of
parts, suitability of material, strength of parts, electrical control,
thermostatic arrangement, reliability of automatic features and positiveness
of ignition.
B. Any combination of gas burners, attachments or devices
used together in any manner shall meet the requirements which apply
to individual pieces of equipment.
C. All gas burners, devices, attachments and accessories,
covered by this section, shall bear the manufacturer's identification
marking.
No devices or attachment shall be installed
on any gas burner which may in any way impair the combustion of the
gas.
No devices employing or depending upon an electrical
current shall be used if of such character that failure of the electrical
current could result in the escape of unburned gas or in failure to
reduce the supply of gas under conditions which would normally result
in its reduction unless other means are provided to prevent the development
of dangerous temperatures, pressures or the escape of gas. Only approved
devices and controls may be used.
A. Electrically operated safety devices shall not depend
upon the closing of a circuit to shut off the main gas supply. (This
requirement shall not be construed as prohibiting the use of electrical
regulating devices, provided the required safety devices are also
installed.)
B. All electrical work and equipment of the system shall
be in accordance with the requirements of the Electrical Code of the
Village of New Haven, Michigan.
All gas burners shall be located so that they
will be readily accessible for operation, repair and adjustment and
for maximum safety.
A. Gas burners shall be installed so that their continued
operation shall not raise the temperature of surrounding combustible
materials or construction more than 90° F. above normal room temperature.
B. Equipment with closed bases, in which no provision
is made for the circulation of air below the burner boxes or combustion
chambers, shall be properly insulated from combustible floors.
C. Clearances.
(1) The minimum clearance of gas-fired heating units from
combustible partitions and materials shall be as set forth in Table
No. 4, except in the case of equipment especially designed for
burning gas and tested and listed for lesser clearances by a nationally
recognized testing laboratory.
(2) The clearance to combustible construction may be reduced
as specified in Table No. 2, where the combustible construction is protected in accordance
with this table.
Gas-fired floor furnaces shall be specifically
approved by the Inspector for services in direct contact with combustible
floors in which they may be installed.
A. Manual main shutoff valve. A separate manual main
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 or the floor furnace.
B. Combustion air. 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 BTUs per hour of gas
input, whichever is the greater, and shall be installed in such a
manner as to ensure proper combustion.
C. Placement. The following are requirements that will
serve in properly placing the furnace or furnaces to serve one story.
(1)
No floor furnace shall be installed in the floor
of any aisle or passageway of any auditorium, public hall, or place
of assembly, or in an exitway from any such room or space.
(2)
Walls and corners. 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.
(3)
Draperies. 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.
(4)
Central location. Generally speaking, the more
central the location the better, favoring slightly the sides exposed
to the prevailing winter winds.
D. Bracing. The floor around the furnace shall be braced
and headed with a framework of material not lighter than the joists.
E. Support. Means shall be provided to support the furnace
when the floor grille is removed.
F. Clearance. 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. When these clearances
are not present, the ground below and to the sides shall be excavated
to form a "basin-like" pit under the furnace so that the required
clearance is provided beneath the lowest portion of the furnace. A
twelve-inch clearance shall be provided on all sides except the control
side, which shall have an eighteen-inch clearance.
G. Access. Provisions shall be made for an access door
to the floor furnace by means of an opening in the foundation wall
of at least 18 inches 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.
H. Seepage pan. Whenever the excavation exceeds 12 inches
or water seepage is likely, a pit made of concrete, waterproof, not
less than 3 3/4 inches thick and extending four inches above
the grade level shall be used. The pit shall be not less than six
feet by six feet inside dimension, with at least 2 1/2 feet of
clearance on the control side and clearance on all other sides of
not less than six inches.
I. Wind protection. Floor furnaces shall be protected,
where necessary, against severe wind conditions.
J. Upper floor installations. 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 provision of Subsection
B, with access facilities for servicing on the control side, with minimum furnace clearances 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.
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:
A. 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 shall be installed and employed.
(1)
Pilot burners shall be supported in such manner
that their position relative to the main burner or burners shall be
fixed.
(2)
Pilot burners shall be so positioned as to be
safely lighted and readily accessible for inspection, cleaning or
replacement.
(3)
Automatic safety pilots of gas burners having
a hourly input of less than 400,000 BTUs shall be so adjusted that
the main gas supply will be shut off within three minutes after a
pilot flame has been extinguished. Gas burners having an hourly input
of 400,000 BTUs 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 10 seconds of pilot flame failure; except that gas-designed
sectional cast-iron boilers will be accepted when provided with an
approved type safety pilot which shuts off the main gas supply within
75 seconds of pilot flame failure.
(4)
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 a normal manner.
(5)
All pilots shall be so adjusted as to prevent
carbon deposits.
B. All warm air furnaces shall be equipped with an approved
high temperature limit device and set not to exceed 300° for gravity
air systems and 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 steam boilers shall be equipped
with approved pressure limiting devices and approved low water cut
off. Limiting devices on water and steam boilers shall be set so as
to not exceed the limitations as specified by the regulations of the
American Society of Engineers. These limiting devices shall be in
addition to operating controls.
C. 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.
(1)
All gas pressure regulators or diaphragm control
valves, used with 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.
(2)
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.
D. An approved manual main shut-off 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 or equipment.
(1)
A pilot gas supply line shall be installed on
the supply side of an approved main burner shut-off device through
an approved fitting and shall be equipped with a shut-off valve and
an adjustable pilot gas pressure regulator.
(2)
Drilling and tapping the fuel line for the purpose
of connecting a pilot gas supply line is prohibited.
E. All gas burners shall consist of factory-assembled
and -tested units.
(1)
Gas burner units shall be so installed or attached
as to prevent twisting, sliding or dropping out of the intended correct
position.
(2)
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.
(3)
Air shutters shall be adjusted to produce a
good flame at the prevailing gas pressure.
(4)
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.
(5)
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 1/3 the full gas rate.
(6)
Burners shall not expel gas through air openings
in mixer faces when operating at prevailing pressures.
F. The combustion chamber and all its passages shall
be gastight.
G. Pressure relief; venting.
(1)
The fuel door of a converted appliance shall
be arranged to relieve pressure due to puffs or backfire caused by
delaying ignition or other causes and shall be provided with an approved
self-closing device.
(2)
Every gas-fired boiler, furnace or other space
heating device shall be effectively vented to the outside atmosphere.
H. 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 gases
through the equipment, which will be locked in such a position as
not to interfere with the safe operation of the burner.
(1)
Every gas-fired boiler, furnace or other nonportable
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 BTUs' 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 (1) ensure the ready escape of the products of
combustion in the event of no draft, backdraft or stoppage beyond
the equipment, (2) prevent a backdraft from entering the equipment
and (3) neutralize the effect of stack action of the flue upon 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.
(6)
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.
(a)
Part 3, Section 5c from ASA Z-21.8 1948.
Clearance from combustible material to gas-fired
space heating unit vent piping shall be such that continued operation
of the equipment will not raise the temperatures of surrounding combustible
materials or construction more than 90° F. above normal room temperatures.
The customer shall be thoroughly instructed
by the vendor or his agent as to proper and safe operations of the
gas burner before it is placed in continuous service, and suitable
printed instructions shall be supplied by the vendor or his agent
and prominently displayed near the gas burner.