Step 4 Set High Fire Gas; Step 5 Set Low Fire Gas; Step 6 Verify Gas Settings - Eclipse TA Series Installation Manual

Step 4: Set high fire gas
Tap "D"
Tap "B"
Step 5: Set low fire gas
Step 6: Verify gas settings
Step 7: Stop Procedure
4
1. If the burner has and is ignited, set the main gas pressure
regulator for 7" w.c. outlet pressure.
2. Drive the main gas control valve to high fire (full open).
3. Verify air flow with the burner firing, repeat Step 2 "Verify air
flow".
4. Make sure that pressure taps B and D are open.
5. Connect the manometer to taps B and D.
6. Measure the gas differential pressure.
7. Use the gas curve from the appropriate ThermAir Data
Sheet for the gas being used to find the differential gas
pressure needed at high fire.
Note:
Select the appropriate gas orifice differential pressure based
upon the desired amount of excess air in the burner.
8. Adjust the adjusting screw on the main gas pressure
regulator to achieve the desired gas flow.
9. Once the chamber conditions stabilize, (i.e. pressure and
temperature), repeat Steps 3 through 8.
10. Remove the manometer.
11. Close the pressure taps.
1. Drive the main gas control valve to low fire.
2. Adjust the control valve linkage to provide the desired low
fire gas flow.
Note:
It is very difficult to measure the very low gas pressures
experienced at low fire, and it may be necessary to rely on
visual inspection of the flame. This is especially true when
gas turndowns in excess of 10 to 1 are being used. The main
intent is to provide a stable flame with good flame signal that
will not cause the chamber temperature to overshoot.
Make sure that all settings are still the same after cycling the
system several times between high and low fire.
Caution:
Do not turn the combustion air blower off until the chamber
temperature is below 250ºF (121ºC). This will prevent hot
gases from back flowing into the burner and blower causing
damage to the burner.
1. Stop the burner through the burner control system.
2. Run the combustion air blower until the chamber
temperature drops below 250ºF (121ºC).
3. Shut off the combustion air blower.
4. Close all manual gas valves to the burner.
Eclipse ThermAir T/A Series v1.10, Installation Guide No. 114, 4/7/06