Eclipse ThermJet TJSR Series Design Manual page 7

High/Low Control
The firing rate is adjusted at two positions, the high and
low fire set points. The burner remains on during the full
process cycle. When the system is set to high/low control:
1. Manual butterfly valve sets high fire air flow rate.
2. Solenoid valve opens for high fire air flow and closes
for low fire air flow.
High/Low Control
(single burner)
High/Low Control
(multiple burners, shut-off by zone)
High/Low Control
(multiple burners, shut-off by burner)
Eclipse ThermJet Self-Recuperative, V5, Design Guide 208, 9/16/2011
3. Manual butterfly valve sets low fire bypass air flow.
4. Manual butterfly valve balances the air flow for burner
(multiple burner installation).
5. Ratio regulator adjusts gas flow as loading line
pressure changes due to air pressure changes.
6. Manual butterfly valve sets high fire gas flow.
Main Gas
Shut-Off
Valve Train
Main Gas
Shut-Off
Valve Train
To Other
Zones
To Other
Zones
Main Gas
Shut-Off
Valve Train
To Other
Zones
Figure 3.1 High/Low Control
To Other
Zones
To Individual
Burner Piping
7