Ref: Dimensions 

&

 Instructions 1857-1

1857-01,-0,-1,-3, and -4

1857-5-F, -6-F, and -7-F

F = fl anged--others threaded

Valve C

v

scfh of 0.6 sp gr

 designation 

co effi

  cients 

gas @ 1"w.c. 



P

1857-01  

19  

1 100

1857-0   

31  

1 800

1857-1   

48  

2 780

1857-3  

130  

7 500

1857-4  

220 

12 700

 1857-5-F 

310 

20 

200

 1857-6-F 

510 

32 

300

 1857-7-F 

870 

52 

000

C

v

 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 
application.

1857 Supervising Gas Valves cannot be used for oil.

The maximum working pressure is 50 psi.

Auxiliary equipment required for complete Supervising 
Valve system:

Solenoid Shutoff  Valves:

 Manual Reset such as North 

American’s 1518.

Pressure Switches:

 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.

8647-01 Filter:

 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:

 Brass.

8647-01 Filter

Sheet 1857

North American Supervising Gas Valves
FM Approved

8657-03

Bleed Orifi ce

ENERG

Y | C

OMBUSITION