How to Install a Wall Mounted Space Heater

Steps for Installing a Wall-Mounted Space Heater

1. Determine a source of constant power nearby to the desired installation location of the heater.
2. Before doing any electrical work, ensure power is turned off at the breaker panel for the active circuits and confirm it’s off with a tester.
3. If using an existing outlet as a power source, remove the cover plate with a screwdriver, then remove the outlet from the box. It may also be necessary to remove the box from the wall.
4. Run 14/2 wiring from the existing outlet to the location of the new heater. It may be necessary to drill through wall studs or other structure.
5. Remove the sheathing on the new wire at the existing outlet, then feed that wire through the electrical box.
6. Strip the conductors on the new wire and either connect them to an available screw on the outlet or splice to existing conductors using wire nuts.
7. Resecure the electrical box in the wall, replace the outlet, and install the cover plate.
8. Strip the other end of the new wire and splice the conductors from the power supply to the appropriate wires in the heater.
9. Install the supplied mounting brackets to the wall, then click the heater onto those brackets.
10. Restore power to the circuit and turn on the heater.

Read our guide on the best space heaters to find the right one for your home.

If the existing electrical box is old work — meaning it was installed after the drywall — it should come out easily, making the splice straightforward. On an Ask This Old House project, the electrician used a thin insulation rod (only an eighth of an inch thick) to probe through the wall cavity and confirm the path between the existing outlet and the heater location before drilling through any studs. This simple step helps avoid surprises inside the wall.

On one Ask This Old House visit, a homeowner had been relying on a portable space heater in a first-floor bathroom that lacked any permanent heat source. While the portable unit got dangerously hot, it was only a temporary solution. A wall-mounted heater, properly wired into the home’s electrical system, provided a safer, permanent fix — freeing up floor space and eliminating the risk of an overloaded extension cord.

Pro Tip: When choosing where to place a wall-mounted heater, consider its coverage angle. As discussed on Ask This Old House, positioning a heater in a corner rather than directly at a workstation allows its wide aperture to cover the entire space — reaching 15 to 20 feet in each direction — rather than heating just one spot.

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