Question 201General Subjects - 1st Asst/Chief

The correct answer is B) Centrifugal pump. In hydronic heating systems, centrifugal pumps are invariably used as circulators. Centrifugal pumps are well-suited for this application due to their ability to generate the necessary pressure and flow to circulate the heated water or other fluid throughout the system. The centrifugal action of the pump impeller efficiently moves the fluid, making it the preferred choice over other pump types like reciprocating, rotary, or diaphragm pumps. The other answer choices are incorrect because they are not the typical pump used in hydronic heating systems. Reciprocating, rotary, and diaphragm pumps have different operating principles and are generally not as well-suited for the specific requirements of a hydronic heating circulator.