Which type of coolant heater is known for rapidly warming the engine?

The type of coolant heater recognized for rapidly warming the engine is known as a circulating heater. This type of heater is designed to heat the engine coolant and promote circulation throughout the engine block and radiator system. By circulating the warm coolant, it ensures that the entire engine warms up quickly and evenly, reducing the time it takes for the engine to reach optimal operating temperature. This is especially beneficial in cold weather conditions, as it helps to prevent engine wear and improve performance by allowing for more efficient combustion as the engine warms.

Immersion heaters, on the other hand, work by being placed directly in the coolant, typically heating a limited volume. Block heaters heat the engine block directly, but both may not circulate the heated fluid as effectively as circulating heaters do. External heaters are used for warming the engine externally but may not offer the same efficiency in warming the engine quickly compared to circulating heaters.