What is recommended as a best practice before firing a boiler?

Ensuring that the boiler has sufficient water before firing it is critical for safe and effective operation. A boiler relies on water to absorb heat and create steam. If the boiler is operated without sufficient water, it can lead to overheating and potential damage to the boiler components, including the heating surfaces. This can result in catastrophic failure, such as a boiler explosion or severe damage to the unit. Proper water levels help maintain the necessary conditions for safe operation and prevent overheating, ensuring efficient performance.

While the other choices, such as checking the burner calibration, electrical connections, and inspecting the exhaust flue, are important maintenance tasks, they do not directly address the fundamental operational requirement of water levels in the boiler. Ensuring sufficient water is the first step in preparing a boiler for firing, making it a best practice that should never be overlooked.