Describe where the water appears
From a safe spot, note whether you see moisture above the tank, at a connection, or only on the floor. Water can travel down the equipment before it pools. Avoid touching the heater or standing in water near electrical components.
Share the model and timing
Let the technician know whether it is a tank or tankless unit and when you first saw the water. Say if the water is still accumulating, whether hot water still works, and whether other units in the building are affected.
Have a technician locate the source
A loose connection and a leaking tank can have very different remedies. A technician can identify the origin and explain what repair or replacement involves.
