What condition can lead to overheating in a boiler?

Low water levels in a boiler can lead to overheating because the boiler relies on water as a coolant to maintain temperature and to transfer heat effectively. When water levels drop below the recommended amount, there is insufficient coolant to absorb and dissipate the heat generated by the combustion of fuel. This lack of water can result in areas of the boiler overheating, potentially leading to serious issues such as tube failure or even explosions. Maintaining proper water levels is crucial for the safe and efficient operation of a boiler, ensuring that it operates within the designed temperature and pressure parameters.