Some of the warning signs of an overloaded surge protector are: The surge protector feels hot to the touch or emits a burning smell. The surge protector makes buzzing or crackling noises or sparks. The surge protector trips the circuit breaker or blows the fuse frequently. The surge protector stops working or fails to protect your devices from power surges. If you notice any of these signs, you should unplug your space heater and surge protector immediately and replace them with new ones.