Blower & Damper

The firebox temperature, as it burns fuel , mostly depends on the available airflow, since oxygen in the air fuels the fire.

The primary way to feed air to the firebox is by opening the regulator and cutoff fully and propelling the vehicle. As the steam is expelled cylinders out into the atmosphere through the chimney, with every gear cycle, it creates a vacuum in the firebox, drawing in fresh air.

However, full acceleration isn't always desirable, which is why there are additional controls to adjust airflow - blower and damper.

Blower is usually operated by a valve. When open, it releases steam from the boiler to the chimney. This creates some vacuum in the firebox, drawing in fresh air. However, since this airflow is vastly inferior to acceleration airflow, the blower is only efficient to use when stationary.

Damper is usually operated by a lever. When closed (pushed down) it chokes the airflow whatsoever, drastically reducing fire temperature, even if the vehicle is accelerating. This is used to intentionally cut steam production when it is no longer needed, although doing so by injecting water is an even better alternative.