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Key to System Schematics
Symbol
Appearance
Name
Remarks
Bulletin/
Info Guide
ThermJet Self-Recuperative
Burner
208
Main Gas Shut-Off Valve
Train
Eclipse strongly endorses NFPA as a minimum
756
Combustion Air Blower
The combustion air blower provides the combustion air
pressure to the burner(s)
610
Air Pressure Switch
The air pressure switch gives a signal to the safety
system when there is not enough air pressure from the
blower
Gas Cock
Gas cocks are used to manually shut-off a supply line
710
Solenoid Shut-Off Valve
Solenoid valves are used to automatically shut off the
fuel or air supply
Manual Butterfly Valve
Manual butterfly valves are used to balance the air or
gas flow at each burner, and/or to control the zone flow
720
Automatic Butterfly Valve
Automatic butterfly valves are typically used to set the
output of the system
720
Adjustable Limiting Orifice
Valves
Adjustable limiting orifice valves are used to balance
the gas flow at each burner.
728/730
Dungs FRG Ratio
Regulator
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 air supply line. The cap must
say on the ratio regulator after adjustment.
Pressure Taps
The schematics shows the advised positions of the
pressure taps
Impulse Line
The impulse line connects the ratios regulator to the air
supply line
Main gas
shut-off
valve train
P
NC