What should be done with the boiler before conducting a hydrostatic test?

Before conducting a hydrostatic test on a boiler, it is essential to fill it with water. This step is crucial because the hydrostatic test is designed to evaluate the integrity of the boiler's pressure boundary by applying internal pressure with water. Filling the boiler allows the test to assess whether there are any leaks or weaknesses in the structure, as the water will reveal any loss of pressure over time.

Filling the boiler also ensures that the pressure is evenly distributed throughout the system. During the test, the water is typically pressurized to a level above the normal operating pressure to help identify any potential issues. A properly filled boiler is a key factor in ensuring accurate and effective testing.

Draining the boiler completely would defeat the purpose of the hydrostatic test, as there would be no fluid to apply pressure with. Heating the boiler to operating temperature is not applicable here since the test is performed at ambient temperature, and checking all fittings is a good practice but is typically done after filling the boiler in preparation for the test. Therefore, filling the boiler with water is the correct procedure before conducting a hydrostatic test.