The bunkers level start problem when bunkering with new coal. The situation seems that the problem occurred due to dust extraction filters too dirty which are covered with wet coal. Therefore the dust extraction filters have been cleaned and serviced by coal and ash maintenance team. After that bunkers level reading back to normal.
I am suspected that hot coaling had caused condensation in bunkers atmosphere and make dust inside the bunker becomes wet. When dust extraction does not function efficiently, wet coal dust accumulates at the bunker level transmitter. On Instrument side, temporary solution for the time being is to service and clean the level transmitter very often.
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