The following is intended as an introduction to power usage in your home and should not replace the specific requirements of your personal appliances or outlets. State and county ordinances govern the codes by which residences are wired and this could not begin to cover every scenario. Additionally, for every rule there is an exception; homes have enjoyed electricity since the early 1900s and while yours may not be that established, when it comes to wiring there may be more exceptions than rules.
Most homes are run by a three-wire service that consists of two hot and one neutral line. Together, these lines provide 240 volts of power, which flows into your service panel. If you were to take a peek inside this box, you may notice switches labeled for the various parts of your home. There will be some that cover a whole room like the bathroom, living room, or bedroom, and others that focus on a single item such as the furnace, water heater, or stove.
Each of these breakers represents a circuit that is either dedicated, that is "dedicated" to a single item, or a branch, which "branches" off and powers several items. Dedicated circuits can run major 240 volt appliances, such as the furnace or range, or they may focus on a single 120 volt high draw item such as the refrigerator or the GFI outlet in your kitchen or bathroom. In an area such as a living room, branch circuits can power a whole room on 120 volts: light fixtures, outlets, and switches. Branch circuits also run on a "daisy chain," which means that as that voltage runs the circuit, all power/amperage used should not exceed the limits. If ever you've had a space heater running while cooking dinner and then stopped to vacuum and found yourself in the dark, you have experienced the product of an overloaded circuit. They are not all powerful!
It is also important to note the run time. Circuits can run at 75% of their maximum capacity indefinitely. They can pull up to100% for shorter periods of time, allowing for the use of a blow-dryer, microwave, vacuum, or space heater/electric fireplace.
Your appliances measure the amount of energy they require in watts. The formula for this conversion is Volts x Amps = Watts, and in the case of the fireplace insert, 120V x 11.67A=1400W. Most standard US outlets can safely support 1500watts. This knowledge, along with a basic understanding of the energy requirements of what you are using is important to understand in order to safely use electricity.
So what sort of usage do you have in your living room? Maybe a TV, router, gaming system, reading lamp, charger, Roomba, and an electric fireplace? Deciding if you are overloading the circuit is as simple as adding! The bigger the television, the more the wattage requirements, but a 60" LED TV uses about 130 watts. Add on to that your PS5 (200W), ceiling fan (70W) and phone charger (6W) and you are well within your limits. Just 406 watts used.
Our fireplace inserts are essentially very pretty space heaters with the same electrical requirements of 120 volts/1400 watts. We power it on and cozy up for the evening with no plans beyond binge watching our favorite show and relaxing. We now know that 1500 watts is the goal, but if our TV and system are using 300 watts and the fireplace is using 1400 watts, it's more than your circuit should handle.
Will it cause a fire? Probably not, but that is little comfort to homeowners who have suffered from electrical fires. There are safety features built in and it is more likely that you will find yourself with a tripped panel or a broken firebox, but it is always best to play it safe. This means limiting the power pulled from each outlet, not overloading the circuit, and listening when your house give you clues that it's too old for such nonsense.
To enjoy a movie night in front of the fireplace, arrange your TV stand so that the fireplace runs on a separate outlet from your other electronics and limit the wattage use. While spreading out the load between outlets will not prevent the circuit from overloading, it will protect the outlet from overheating. If outlets are not spaced in a way that will accomplish this, or if you hope to routinely run your living room fireplace, computer, television and other electronics simultaneously, consider calling a local electrician and having a dedicated circuit run to feed the fireplace's outlet. Never use a surge protector or extension cord with your fireplace insert. These are not designed for high power items.
Lastly, always unplug your fireplace when not in use and routinely check the connection to ensure that there is a snug fit between outlet and plug. A loose connection pulls more power than a tight one! It is recommended that the outlet be switched out if you notice a poor fit.