Why did the Austrian flagship Schwartzenberg withdraw during the Battle of Heligoland?

During the Battle of Heligoland, the Austrian flagship Schwartzenberg was forced to withdraw after sustaining significant damage during a fierce exchange of fire with Danish forces. The Danish squadron concentrated their fire on the flagship, which resulted in several of its guns being dismounted.1

The situation became critical when a shot set fire to the ship's foretopsail. Because the ship's pump had been destroyed, the crew was unable to effectively combat the spreading flames. Consequently, the Austrians were compelled to seek sanctuary in neutral British waters to escape further engagement.1