Groen NGB, Руководство оператора

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Sequence of Operation
A. For Model NGB or NGB/2
Pushing the power switch to the "ON" position will cause the water feed valve to open, filling the generator unit
until the level probe senses the proper water level. The feed valve will then close. At this time, momentarily
pushing the power switch to the "RESET" position Will open the gas valve. Gas flowing from the main burner will
be ignited by the standing pilot flame.
For units made before August 8,1991:
The gas valve will open at a gas pressure of 0.5 inch W.C. Within 15 seconds the pressure should reach 3.5
inches W.C. for natural gas or 10.0 inches W.C. for propane.
For units made after August 7,1991:
The valve will open at a gas pressure of 0.9 inch W.C. for natural gas or 2.5 inches W.C. for propane. Within 15
seconds the pressure should reach 3.5 inches W.C. for natural gas or 10.0 inches W.C. for propane.
The air vent is open at this point and will remain open until the temperature in the generator reaches 200°F. As
evaporation occurs in the generator and the water breaks from the probe, the water feed valve will open and the
20 second time delay will activate. If the water level fails to rise to the probe before the time delay times out, the
gas control valve will close and the controls will nave to be reset manually. In normal operation, the water level
will rise to the probe within the time delay period, and there will be no interruption in
heating.
When pressure in the generator reaches 10 PSI, the operating pressure switch will cause the gas valve to close.
If residual heat makes the pressure rise to 12 PSI, the mid-range pressure switch will open both the condenser
water valve and the blow-down valve to decrease the pressure rapidly. As steam pressure decreases below 10
1/2 PSI. the mid-range switch will cause the condenser and blow-down valves to close. When the pressure falls to
9 PSI, the operating pressure switch will open the gas valve, and heating will resume. After this heating and
cooling cycle has been repeated once or twice, the generator will operate between 9 and 11 PSI, if no steam is
being drawn from it.
If steam pressure reaches 14 PSI. the high limit pressure switch will open and lock out the controls. When this
happens, the pilot lamp will go out. An open high limit switch must be reset manually to start the unit again.
Should the pressure exceed 15 PSI at any time. the safety valve will open and relieve excess pressure.
When the power switch is turned to the "OFF" position, the gas valve will close and the drain valve will open.
draining the unit completely.
B. For Model NGB/E or NGB/2/E
The sequence of events is the same as for Model NGB, with the following exceptions.
Pushing the power switch to the "RESET" position will activate the Carborundum ignition coil. The coil will heat to
a glowing temperature and cause the gas valve to open within approximately 12 to 20 seconds. Gas flowing from
the burner will be ignited by the coil. When the flame sensor detects a flame, the coil will] deactivate. If the sensor
ceases to sense a flame, the gas control valve will close and shut off the main burner. Then the coil will be
energized again and will relight the burner.
During normal operation, when steam pressure falls to 9 PSI, the operating pressure switch will activate the coil
and initiate the ignition sequence.
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