What is wrong with electric central heating unit if the fan will not come on at all?

If the fan in an electric central heating unit won't come on, it could be due to a faulty fan motor, a blown fuse, or a tripped circuit breaker. Additionally, a malfunctioning thermostat or a problem with the control board could prevent the fan from operating. It's also possible that the unit is not receiving power due to electrical issues. Checking these components can help identify the problem.