Harsco Industrial MODU-FIRE FORCED DRAFT N750, Инструкция по установке и эксплуатации

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MODU-FIRE® Forced Draft Gas-Fired Boiler
37
5.6 T
ROUBLESHOOTING
If any “Manual Reset” limit device trips,
DO NOT RESET
without determining and correcting the cause.
(Manual Reset Limits include: Flame safeguard,
high or low gas pressure, high temperature limit,
stack temperature.)
5.6.1 Loss of Power
In the event of loss of power, the entire boiler system is de-energized, closing all automatic valves and halting all
boiler operations. When power is restored the sequence of operation will resume at Step 3, provided that all the limits
are satisfied.
5.6.2 Loss of Water Flow
When there is insufficient water flow to close the flow switch, the burner operation is interrupted and the control
displays LOW FLOW / ILK. When water flow is re-established, the sequence returns to Step 3, provided that the
other limits are satisfied. This error also indicates that the interlock jumper is removed or the interlock is wired to an
open device.
5.6.3 Low Gas Pressure
The low gas pressure switch opens when there is insufficient gas pressure available for proper operation of the boiler.
LOW GAS PRESSURE is displayed, and burner operation is interrupted. If a gas-supply shut-off valve is closed for
any reason, a low gas condition will result. When gas pressure is restored, LOW GAS PRESSURE will remain on the
display panel. A manual reset is required to restart the boiler, provided that all other limits are satisfied.
5.6.4 High Gas Pressure
The high gas pressure switch opens when there is excessive manifold gas pressure for the proper operation of the
boiler. HIGH GAS PRESSURE is displayed and the burner operation is interrupted. When proper gas manifold
pressure is restored, HIGH GAS PRESSURE remains on the display panel. A manual reset is required to restart the
boiler, provided that all other limits are satisfied.
5.6.5 High Water Temperature
When the boiler water has exceeded both the operating and high-limit temperature the high limit switch opens, and
HIGH LIMIT is shown on the display. When the water temperature falls below the high-limit temperature, the boiler
will remain locked out until the water high limit switch is manually reset and the front panel reset button is pressed.
Once the switch and the control are reset, the sequence returns to Step 3 to await heat demand provided that the
other limits are satisfied.
5.6.6 Low Air
The air switch has been factory set and should not be adjusted in the field.
If the display panel indicates AIR SWITCH NOT OPEN or AIR SWITCH NOT CLOSE this indicates improper airflow
through the boiler. Check the hoses leading to the air switches. Verify proper blower operation. An air switch error
does not necessarily mean that the air switch is defective.