Furnaces generally.
All floor furnaces, central heating
units, suspended heating units, insert type wall furnaces such as
Panelray and all controls shall be approved by A.G.A. or the National
Board of Fire Underwriters. All controls on boilers shall be approved
by the A.G.A.
All floor furnaces, central heating units, suspended heating
units, and boilers used for heating equipped with manually operated
or automatic temperature controls shall be equipped with safety pilot
controls that will shut off the gas to the main burner in the event
the pilot is extinguished or blown out.
All heating units with a fan to furnish heated air to various
rooms in a house or building shall be equipped with a heat limit control
switch located in the discharge side of duct and as near the heating
units as possible. In the event of fan or motor failure, the heat
limit control switch will act as a limiting protection device. Such
heat limit control shall be such type that it cannot be set above
2500 F. The safety pilot shall be connected so that a failure in pilot
will shut off gas supply to main burner.
No heating unit or controls shall be placed in a closet, room
or any other enclosed space without providing ventilating openings
as required by A.G.A. at both top and bottom of enclosure equivalent
to 12 square inches each for appliances having 40,000 Btu input or
less, and 1 square inch additional per 1000 Btu input shall be provided
both top and bottom for appliances having more than 40,000 Btu input.
Inlet and outlet ducts shall be connected to heating units located
in such enclosed spaces. All heating supply ducts shall be constructed
of metal in all residential or buildings of frame construction, and
shall extend from the heating unit to the grill openings. All return
air ducts shall extend from the heating units through the wall or
floor of the room in which the heating unit is installed, and ducts
shall be of metal.
A gas fired unit heater with propeller fan attached shall not
be used as an insert type of duct heater. A unit heater shall not
be attached to a warm air duct system unless listed by A.G.A. for
such installation.
All heating appliances equipped with a gas regulator or a gas
operated diaphragm valve shall have a relief or vent line installed
from the regulator or diaphragm valve back to the main burner of the
appliance.