Questions about operating the 493 as an oil burner

Jerry Day was gracious enough to share his cab ride video of the 493.

It promptly generated a couple of questions.

The first is what was the fireman doing with the hose? He stuck it out the window and opened a valve.

My second questions is periodically the tiny door to the firebox was open. Later it would be closed and then later open again.
What is the purpose for doing that?

It might not look particularly physically demanding, but in paying close attention to the crew operating the 493, they make constant tiny adjustments. It appears operating the 493 as an oil burner is mentally challenging. It must require considerable attention and a great knowledge of the route.