The installation of an electric fireplace insert may not require professional help, but any installation of an electrical outlet within the firebox of an existing fireplace should be undertaken by a licenced electrician.
An electric fireplace insert is designed to sit both within and just in front of the firebox of an existing fireplace.
Electric inserts will have a back area that you’ll need to push through into the opening of the existing fireplace.
Electric inserts will also typically have a widened front area that you push up against the outer wall of the fireplace to provide a flush finish.
Depending on your model of electric fireplace insert you may not need to do anything more than leave the appliance pushed up against the fireplace opening, but some may require connection to the existing fireplace using brackets etc. Check the owner’s manual for guidance.
Furthermore, an electric fireplace insert may come with a removable front trim.
Depending on the model of insert and the situation, this trim can either be installed before or after the insert itself have been installed.