1857-01,-0,-1,-3, and -4
1857-5-F, -6-F, and -7-F
F = fl anged--others threaded
scfh of 0.6 sp gr
gas @ 1"w.c.
valve co effi
cient is a valve’s capacity, in gpm of 60°F
water, for 1 psi pressure drop.
Explosions that occur in multi-burner gas fi red industrial fur-
naces when they are being lighted are frequently the result of
someone carelessly leaving a gas burner shutoff valve open
aft er the previous shutdown. This can allow the furnace to be
fi lled with unburned fuel as soon as the main valve is opened.
Danger of such explosions is substantially reduced by using a
Supervising Gas Valve at each burner.
A Supervising Gas Valve is drilled with a small secondary
passage located so it is open only when the main passage
is closed. A checking pressure line is connected through the
secondary passage of each valve to a pressure switch at the
end of that line. The switch cannot close a circuit to the solenoid
shutoff valves unless all supervising valves are completely
closed. If the solenoid shutoff valves cannot be opened, a
supervising valve is probably open. It must be closed and the
furnace purged before any pilots or burners are lighted.
Required equipment is simple to install and operate. It should
be arranged to check pilots as well as main burners. Solenoid
shutoff valves are wired to close off fuel supply in the event of
air or fuel pressure failure.
In the interest of safety, Fives joins NFPA and insurance
underwriters in urging the use of electronic fl ame supervision
on most fuel burning applications. The decision whether or
not to incorporate an 1857 Valve system rests with the owner
and his insurance underwriter. If desired, Fives can provide
information concerning standards as they apply to your
1857 Supervising Gas Valves cannot be used for oil.
The maximum working pressure is 50 psi.
Auxiliary equipment required for complete Supervising
Solenoid Shutoff Valves:
Manual Reset such as North
From Bulletin 8757, select an approved
normally open switch for the checking line. Also use normally
open switches for low gas and low air protection; the high gas
pressure switch is normally closed.
Body is zinc plated steel. Replaceable fi lter
car-tridge (2-4920-1) is steel and cellulose, impregnated with
phenolic resin. Maximum temperature 275°F.
8657-03 Bleed Orifi ce:
North American Supervising Gas Valves
Bleed Orifi ce
Y | C