Common causes of an electric water heater not working or running out of water too quickly include a blown fuse, tripped circuit breaker, a faulty thermostat or heating element, or the water heater is undersized and cannot produce adequate hot water for the home. To identify the cause of the water heater not functioning properly, it is best to contact a licensed plumber or electrician. A professional plumber or electrician can diagnose the issue correctly and determine if the water heater can be repaired or needs to be replaced. Learn about common causes of an electric water heater not functioning properly and resolutions.