Question 414General Subjects - 1st Asst/Chief

The correct answer is D) When filled, the heat source to the settling tank should be cut in until the ideal settling temperature is reached, then secured allowing the fuel to remain undisturbed for as long as possible. This is the correct practice because maintaining the ideal settling temperature, typically around 95-104°F (35-40°C), is important to allow for proper separation of water and sediment from the heavy fuel oil. Once the ideal temperature is reached, the heat should be secured to avoid disturbing the settling process and allow the contaminants to fully separate by gravity. Keeping the fuel undisturbed for an adequate period is crucial for effective settling. The other options are incorrect as they either keep the heat on constantly, disturb the settling process, or do not provide any heat at all, which would not achieve the necessary temperature for proper separation.