| Other than taking a scale thickness through a zinc plug opening of the water box of a feed water heater of a flash evaporator, what would be the BEST indication for a need to remove scale build-up? |
| A) A drop in the feed water heater shell temperature and a rise in the feed water heater shell absolute pressure (decrease in vacuum). |
| B) A rise in the feed water heater shell temperature and a drop in the feed water heater shell absolute pressure (increase in vacuum). |
| C) A drop in the feed water heater shell temperature and a drop in the feed water heater shell absolute pressure (increase in vacuum). |
| D) A rise in the feed water heater shell temperature and a rise in the feed water heater shell absolute pressure (decrease in vacuum). |
