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7. Operation
Preparing
1. Check to confirm that all the gas cocks have been closed.
2. Check for in-pipe gas leakage with air or nitrogen.
3. Check to confirm that each component unit of the air and gas lines are in normal operation.
4. Check to confirm that gas is being supplied under the specified pressure and that the inside of the pipe has
been subjected to replacement purge.
5.
Start the blower, and confirm that the rotational direction is correct and the exit pressure is as per
specified
6. Set the pressure to the pressure in the maximum combustion
(
6 KPa
)
and to the pressure of the minimum
combustion
(
0.1, 0.5 KPa
)
by using the damper.
7. Fully open the control damper, and air-purge the inside of the furnace.
(
Use approx. 3 times as much as the
furnace volume as the reference volume of air-purge.
)
8. Set the control damper to the position for the minimum combustion.
Igniting
9. Check to confirm that the cock, solenoid valve and limitting valve located immediately before the burner
have fully been closed.
10. Fully open the cock and solenoid valve located immediately before the burner, slowly open the regurating
cock, and check to confirm that the main burner has exactly been ignited.
(Be sure to check them visually or by using a flame detector.)
Adjusting
11. Read the air quantity referring to the burner air quantity characteristic table
(
burner PQ characteristic table
)
12. Calculate the necessary gas quantity, and adjust the gas quantity by using an orifice flow meter
(
MO
)
or other
flow meter and manipulating the limiting valve until the specified excess air ratio is obtained.
13. When the equalizing valve method is used, slowly open the control damper to the position for the maximum
combustion while checking the combustion state, and check to confirm the flowrates of gas and air.
14. When a safety circuit has been incorporated into the flame detector, also check to conform the flame current
value.
15. After setting the excess air ratio, return the control damper to the position for the minimum combustion.
16. When the control motor is used, joint the control damper to the specified position.
