MBW VAPOR EXTRACTION UNIT, Operator'S Safety And Service Manual

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3. While watching LEL percent on sensor or bar graph
on control panel, slowly begin opening vacuum
supply valve.
WARNING
Gas stream through the VEU must remain below
25% LEL. If Low alarm is triggered, close vacuum
supply valve, open bypass valve, and start at step
3. If High alarm is reached, engine will shut down.
Engine will not start until LEL is below 50%.
4. After vacuum supply valve is open fully, run engine
up to full throttle, and begin to slowly close the bypass
valve. See note above. Operating point will be
determined by these factors:
•Configuration of probes
•Gas concentration in ground
• Recommended engine speed
•Recommended vacuum level
5. After bypass valve is closed fully, run engine as
needed to evacuate ground of gas.
6. If desired, turning off individual probes can help
locate leak.
Stopping Engine
1. Fully open air-bypass valve to unload engine.
2. Move throttle to idle position.
3. Let engine idle for one or two minutes.
4. Press engine stop button, or turn off toggle switch.
WARNING
Always stop the engine before:
Adding fuel.
Leaving the equipment unattended for any
amount of time.
Before making any repairs or adjustments to the
machine.