4 Things to Know About Extension Cords and Space Heaters

A 16-gauge extension cord is too thin for a space heater A 1500W heater draws about 12.5 amps, but a 50-foot 16-gauge cord is only rated for about 10 amps. Voltage drops over that distance, causing the cord to overheat, especially at the plug.

The cord heats up because of resistance More current plus more resistance equals more heat. A lamp draws under 1 amp, so it’s fine, but a space heater pushes the cord past its safe limit.

This is not a defect You are asking a wire designed for light-duty use to carry near its maximum rated current over a long run. The National Electrical Code limits 16-gauge to about 10 amps at 50 feet for a single device.

Use a 12-gauge cord or plug directly into a wall For a space heater, use a 12-gauge cord, or better yet, plug the heater directly into a wall outlet. Extension cords and space heaters do not mix.