Final answer:
Low water can occur in a hot water boiler for various reasons, such as insufficient water filling, leaks in the system, and high water temperature.
Step-by-step explanation:
Low water can occur in a hot water boiler, and there are several reasons why this can happen. One reason is if the boiler is not filled with enough water to begin with, which can occur due to a malfunction or improper maintenance. Another reason is if there is a leak in the boiler system, causing the water level to drop. Finally, if the water temperature is too hot, it can cause evaporation and result in low water levels.