Question for an electrician

Tailgate

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New electric fireplace coming. Plugging into an outlet with a 20 amp breaker. There are already about 500 watts on this circuit, tv, sound bar, lights, fan. The fireplace (Orion Traditional 30") shows 1465 watts. Rounded up to 2,000 total, calculates a total of 16.7 amps or 83% of the 20 amps with everything on. Comes in right at code. My math says I should be fine but is there something I'm missing? Don't want to make a mistake or have to dedicate a new circuit to it. Thumbs up or thumbs down?
Many thanks for an answer. Cheers.
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I'm not an electrician, but when I built my shop I put in a small electric water heater (few gallons) for the bathroom sink. IIRC, my electrician pointed out that it was ~82-83% of circuit load and wasn't suppose to be over 80% to meet code. He was OK with it (as was I) and it has never tripped the breaker to date.
 
You will be fine. So, the question to you, are going to be having everything running on the 20A breaker at one time.
 
I would see if it is feasible to run another circuit to the location. Your load would be 83% of capacity and NEC calls for 80% max load which is even more important with a constant load such as the heater which will possibly be run unattended at times. At least look into offloading some of the load to a nearby existing circuit if possible. You can test the entire load out on a kill-a-watt meter to see what the actual load would be with everything in use.
 
I would first check to see if the existing circuit has #12 wire. If not, run a new circuit with #12 wire and 20 amp breaker just for the fireplace. If the existing circuit is #12 wire, you’re probably ok, but I’d still look into moving the tv, sound bar and whatever else to a different circuit.
 
I would first check to see if the existing circuit has #12 wire. If not, run a new circuit with #12 wire and 20 amp breaker just for the fireplace. If the existing circuit is #12 wire, you’re probably ok, but I’d still look into moving the tv, sound bar and whatever else to a different circuit.
+1 Many house circuits are actually 15 amps, and not 20 amps, so double checking is a good idea.
 
New electric fireplace coming. Plugging into an outlet with a 20 amp breaker. There are already about 500 watts on this circuit, tv, sound bar, lights, fan.

What kind of lights are in the circuit? I ask because most TV's are less than 120 watts, the soundbar is likely less than 5 watts, and a fan can't be very much either.

How do you get 500 watts usage with these items?
 
I have an electric fireplace housed in a cabinet with the TV and sound bar sitting on the top. We have been using them for about 8 years on a 20 amp service. It has been working without any issues so far but I'm not an electrician.
 
Last time I read through the NEC, I seem to recall that 80% referring to permanently installed loads, hardwired in other words.

Plug-in devices can go beyond 80% just fine. The breaker will trip if you draw excess current...
 
Last time I read through the NEC, I seem to recall that 80% referring to permanently installed loads, hardwired in other words.

Plug-in devices can go beyond 80% just fine. The breaker will trip if you draw excess current...
Green Acres time.
 
If it's feasible I would run a separate circuit for a big load like this just on general principles. But I do my own work, so the cost would be minimal.
 
I would see if it is feasible to run another circuit to the location. Your load would be 83% of capacity and NEC calls for 80% max load which is even more important with a constant load such as the heater which will possibly be run unattended at times. At least look into offloading some of the load to a nearby existing circuit if possible. You can test the entire load out on a kill-a-watt meter to see what the actual load would be with everything in use.
Nailed it. The extra 20% is for a very temporary surge such as a dehumidifier more starting up, not a continuous draw. That fireplace needs its own circuit.

Assume the standard 120 volts AC. 1,465 watts divided by 120 volts AC = 12.2 amps.

12.2 amps divided by a standard 15 amp house circuit = 81.2 amps. That close to the 80% is not a coincidence; it's a design decision.
 
Last time I read through the NEC, I seem to recall that 80% referring to permanently installed loads, hardwired in other words.

Plug-in devices can go beyond 80% just fine. The breaker will trip if you draw excess current...
First off you hope the breaker will trip. You do need to confirm the wire size as it is common for people to put in a 20 amp breaker on a circuit wired for 15.

Finally you need to consider how many outlets might be on that circuit that you don’t know about but there are testers that can show you.. if you might accidentally overload the circuit with a vacuum cleaner, space heater or a bunch of electronics in the future if you didn’t realize there are 8 outlets on the same wire….
 
When we had a fireplace blower put in (wood fireplace already, just added blower, not an electric fireplace) we put in separate circuit with it's own dedicated fuse. County required that.
We were finishing basement; it fully met code.
 
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