CAUTION! If your lights are dimming or flickering after turning on a large appliance (but your circuit breaker has not tripped), this could mean the voltage in your household is not up to standard. This is a dangerous situation that requires the immediate attention of a professional electrician like Mr. Electric. The other possible cause is loose wiring. If you check your circuit breaker and the wiring looks loose, it’s time to call a professional. Loose wiring is the third-leading cause of home structural fires in the United States.