Eclipse RatioAir v1 - Design Guide No. 115, 2/14/05
19
RatioAir
Main Gas Shutoff
Valve Train
Gas Cock
Solenoid Valve
(normally closed)
Fuel Orifice Meter
Adjustable Limiting
Orifice
Pressure Regulator
Eclipse Combustion, Inc.
strongly endorses NFPA as a
minimum
Gas cocks are used to
manually shut off the gas
supply on both sides of the
main gas shut-off valve train.
Solenoid valves are used to
automatically shut off the gas
supply on a bypass gas system
or on small capacity burners.
Fuel orifice meters are used to
measure gas flow.
Adjustable limiting orifices are
used for fine adjustment of gas
flow.
NC
K
EY
TO
S
YSTEM
S
CHEMATICS
These are the symbols used in the schematics.
756
710
760
910
684
742
Symbol
Appearance
Name
Remarks
Bulletin/
Info Guide
A ratio regulator is used to control
the air/gas ratio. The ratio
regulator is a sealed unit that
adjusts the gas flow in ratio with
the air flow. To do this, it measures
the air pressure with a pressure
sensing line, the impulse line. This
impulse line is connected between
the top of the ratio regulator and
the burner body.
A pressure regulator reduces
gas pressure to a stable, usable
pressure.
Ratio Regulator
