Why Does My Space Heater Only Work in GFCI?

Space heaters are a popular and convenient way to provide supplemental heating in homes and offices, but they can also pose a significant electrical safety risk if not used properly. One common issue that space heater users may encounter is that their heater only seems to work when plugged into a Ground Fault Circuit Interrupter (GFCI) outlet. This article will delve into the technical details of why this phenomenon occurs and provide a comprehensive guide on troubleshooting and resolving this problem.

Understanding GFCI Outlets and Space Heaters

GFCI outlets are designed to protect users from electrical shock by constantly monitoring the flow of electricity and quickly cutting off power if it detects a ground fault. This occurs when there is an unintended path for electrical current to flow to ground, which can happen due to a variety of reasons, such as a damaged power cord or a malfunctioning appliance.

Space heaters, on the other hand, are high-power electrical devices that consume a significant amount of current, typically ranging from 1,000 to 1,500 watts. This high power draw can cause issues with GFCI outlets, as the sudden surge of current when the heater is turned on can sometimes trigger the GFCI’s ground fault detection, causing the outlet to trip and cut off power to the heater.

Factors Affecting Space Heater and GFCI Compatibility

why does my space heater only work in gfci

Several factors can influence the compatibility between a space heater and a GFCI outlet, including:

  1. Heater Power Consumption: As mentioned earlier, space heaters with higher power ratings (1,000 watts or more) are more likely to cause GFCI outlets to trip due to the high current draw.

  2. Heater Element Design: The type of heating element used in the space heater can also play a role. Older-style coil heating elements are more prone to causing GFCI issues compared to modern, more efficient designs like ceramic or infrared heating elements.

  3. Heater Condition: A space heater with a damaged or worn-out power cord, or other internal issues, may be more likely to cause ground faults and trigger GFCI outlets.

  4. GFCI Outlet Sensitivity: The sensitivity of the GFCI outlet can also be a factor. Some GFCI outlets are more sensitive than others, and may be more prone to tripping when a high-power device like a space heater is connected.

  5. Electrical Wiring and Grounding: The quality and condition of the electrical wiring and grounding in the building where the space heater is used can also impact the compatibility with GFCI outlets.

Troubleshooting and Solutions

If you find that your space heater only works when plugged into a GFCI outlet, here are some steps you can take to troubleshoot and resolve the issue:

  1. Check the Manufacturer’s Recommendations: Consult the user manual or product specifications provided by the space heater manufacturer. They may have specific guidance on the recommended electrical requirements, including whether the heater should be used with a GFCI outlet.

  2. Inspect the Space Heater: Carefully examine the space heater for any visible signs of damage, such as frayed cords, broken plugs, or other issues. If the heater appears to be in good condition, move on to the next step.

  3. Test the Space Heater on a Non-GFCI Outlet: Try plugging the space heater into a standard, non-GFCI outlet to see if it still works. If the heater functions normally on a non-GFCI outlet, the issue may be with the GFCI outlet itself.

  4. Check the GFCI Outlet: Ensure that the GFCI outlet is properly installed and functioning correctly. You can test the GFCI outlet using a GFCI tester or by pressing the “test” button on the outlet. If the GFCI outlet is not working properly, it may need to be replaced.

  5. Consider Upgrading the Electrical Wiring: If the building’s electrical wiring is old or of poor quality, it may be contributing to the compatibility issues between the space heater and the GFCI outlet. In this case, it may be necessary to have a licensed electrician upgrade the wiring to ensure proper grounding and reduce the risk of ground faults.

  6. Use a Non-GFCI Outlet: If the space heater is not compatible with GFCI outlets, you may need to use a standard, non-GFCI outlet. However, it’s important to ensure that the outlet is properly grounded and that the space heater is used with caution to avoid any potential safety hazards.


The issue of a space heater only working in a GFCI outlet is a common problem that can be attributed to the high power consumption of these devices and the sensitivity of GFCI outlets. By understanding the technical details, following the manufacturer’s recommendations, and troubleshooting the various components, you can often resolve this problem and ensure the safe and efficient operation of your space heater.


  1. GFCI Outlets and Heating Elements
  2. GFCI Problem with Space Heater
  3. Why Would Something Require a Non-GFCI Outlet?
  4. GFCI Outlets: What You Need to Know
  5. How to Install a GFCI Outlet
  6. How to Install a GFCI Outlet