Wondering if multiple 20 amp outlets can be installed on a 20 amp circuit (AFCI)? The builder installed 20 amp outlets everywhere! Including on 15 amp circuits.
The 15 amp circuit is a no go. My thought is multiple 20 amp breakers can allow too many high amp devices on the same circuit (most likely will never actually happen in a residence) but wondering if NEC will have anything to say about this.
Also, do folks call out non TR outlets for new build?
On a 15 amp circuit, that 20 amp receptacle will never get more than 15 amps from the breaker.
Depends on the location of the build. If it is in a jurisdiction that follows codes, yes, but only if they have adopted the section for tamper resistant outlets. If there is a green tag for electrical inspection on the panel cover, no, I don’t fight with the city inspector. If you are in a rural district with no authority or permits, all you can do is make a recommendation to the buyer.
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Ok thanks for the response. Yeah, very rural in a state that does not have much for code enforcement for residential.
What’s your thought on 20 amp outlets everywhere? Worth noting in a report? I told the buyer it is odd to see them everywhere.
If you concern is overloading the circuit, that would be determined by a load calculation, which is beyond the scope of a home inspection.
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According to the NEC in a dwelling on a 20 amp circuit there is no limit as to the number of 15 or 20 amp duplex receptacles permitted on the circuit. As Adam stated a 20 amp duplex cannot be on a 15 amp circuit, although a 20 amp single receptacle is permitted on a 15 amp individual branch circuit.
As long as the 20 amp duplex receptacles are on a 20 amp circuit there is nothing to report.
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There is no limit to the number of devices that can be on a circuit.
Every 15 amp circuit has the same condition: if you plugged two space heaters into each one, you’re SOL.
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20 amp devices in a dwelling are a waste of money because no one will ever plug in something that has a 20 amp plug. The fact that they used 20 amp circuits is a good thing. That gives an extra 5 amps of capacity on the circuit when compared to a 15 amp circuit. 20 amp circuits with 15 amp duplex receptacles is what I would install in my own home. Also the #12 AWG conductors will have a lower voltage drop.
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How about those that plugin space heater?
Do they have 20 amp plugs on them?
The only inspections I have ever seen a 20 Amp plug configuration is in industrial/commercial inspections.
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Now that you said this, they are going to pop up on you as it did for me today. I cannot remember the last time I had seen this in a residential home.
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Those are all mostly 1600 Watts, or 13.33 amps.
But be sure the ground plug is the right way around, or the opposing currents will be twisted, and electrons will sluff off the insulation leading to overheating of the tubes.
I see 20amp receptacles in homes occasionally, but never the plugs. I have only seen the plugs in industrial/commercial inspections.
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You said plugs and my mind said receptacle 
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In the US portable electric heaters are limited to 1500 watts, which is roughly 13 amps.
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And they would have a 15 amp attachment plug which means that a 20 amp receptacle on a 20 amp circuit in a dwelling would never really be needed.
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Would they be able to tolerate more heat at the outlet?
I’ve seen many outlets that were scorched where heaters were plugged in.
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It is important to understand that, the amperage of an outlet/receptacle socket does not exceed the amperage of the circuit it is on. That said, both 15 amp and 20 amp electrical outlet/receptacle sockets may be installed onto a 20 amp circuit. By the same token, only 15 amp outlet/receptacle sockets should be used for 15 amp circuits.
Good question. 20 amp receptacles are usually specification grade meaning that the internal components are higher quality so they will last longer and maintain proper spring tension on the plug. Both 15 and 20 amp receptacles are designed to carry the load based on their configuration but cheap junk devices won’t last as long.
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Indirectly, yes. The cheapest builder grade outlets are the ones with heat problems, and the 20A as far as I can tell are only sold in the higher grades.
A quality 15A and quality 20A outlet are otherwise the same internally. The 20A has a weird prong shape on one side, which can only reduce the contact area thus increase heat. Also note that 15A outlets are rated to pass 20A: you can put 15A in the chain with 20’s and mix them up freely.
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