A solar electric heater is installed in the water tank on the roof.
The light on your electric heater socket means that your socket is charged. Just check whether the electric heater circuit plug is connected correctly, otherwise the electric heater may be broken.
Electric heating is very slow. The temperature only rises about 10 degrees in an hour. Are you too impatient?
An electric heater costs around tens of dollars. You can buy them anywhere solar water heaters are sold. It will take time and effort to get someone to replace it.
Two situations: 1. The wires are in poor contact and need to be repaired.
2 The electric water tank heater is broken and requires professional service personnel to repair and replace it. Because damage to the electric heater may result in some contaminationtion of water, so for the safety and health of your family, I hope you can find a professional team to test as soon as possible. Hope they can help you!