A 15 amp receptacle is tapped off a 20 amp receptacle using 14 AWG wire.
As far as I could tell the circuit was wired with 12 AWG. The breaker size was 15 Amps.
Is this OK?
My concern is that in the future a 20 Amp breaker may be used to replace the 15 Amp since 12 AWG is used as viewed from the panel box.
As long as you know the circuits OCPD is rated at 15A their is really nothing wrong here. Yes, it is a valid concern to know that someone could get into the panel and increase the OCPD to a 20A and this the 14 AWG that is tapped will then be a violation and a hazard.
It is generally fine for the conductor to be larger…but the weakest link in the circuit is what has to be protected with the OCPD so it would have to stay with a 15A breaker…again in the end it is fine as it stands and really can’t report on a concern that COULD happen…if while it stands now it is compliant.
valid concerns but again done all the time…personally I would have liked to see them tap with 12 AWG…as they could say it was done to control voltage drop…which happens alot when people run 12 AWG to a 3rd floor and then change over to 14 AWG…the key is the OCPD in this case and you have verified it is sized for the 14AWG Tap…and 15 AMPS.
Thanks Paul
I’ve been sold a bridge with this explanation too… so don’t read further if you don’t have a grasp on electrical codes, since this might mess up a person.
I was explained having 14# wire on a 12#/20amp circuit is ok. Because 14# is an ok tap off a 20 amp circuit, as long as it doesn’t feed a device more than that 14# rating. This case 15amps. So 14# pigtails are ok feeding 15amp receptacles on a 20 amp circuit (as long as it is not the only receptacle in the branch). This is why 15amp rated receptacles can be on a 20 amp circuit.
I don’t do this(use lower rated pigtails), and only met one person that was comfortable with it. Paul do you have an option? 
tom <ducking and running!>
lol…Don’t duck and run…lol…Love these questions…
Are you refering to this in your question:
Other Loads.
Branch-circuit conductors that supply
loads other than those specied in 210.2 and other than
cooking appliances as covered in 210.19(C) shall have an
ampacity sufficient for the loads served and shall not be
smaller than 14 AWG.
Exception No. 1: Tap conductors shall have an ampacity sufficient for the load served. In addition, they shall have an ampacity of not less than 15 for circuits rated less than 40
amperes and not less than 20 for circuits rated at 40 or 50
amperes and only where these tap conductors supply any of
the following loads:
(a) Individual lampholders or luminaires fixtures) with taps extending not longer than 450 mm (18 in.) beyond
any portion of the lampholder or luminaire fixture).
(b) A Fixture having tap conductors as provided in 410.67.
(c) Individual outlets, other than receptacle outlets, with
taps not over 450 mm (18 in.) long.
(d) Infrared lamp industrial heating appliances.
(e) Nonheating leads of deicing and snow-melting cables
and mats.
Exception No. 2: Fixture wires and flexible cords shall be
permitted to be smaller than 14 AWG as permitted by
240.5.
Generally many know that you can have a 15A receptacle on a 20A circuit because the 15A rating of the device will never exceed the 20A rating of the conductor…however on a true 15A circuit you can’t use a 20A receptacle for it’s use…however good news is most are dual rated 15/20A…so all is good…lol
Table 210.21(B)(3) Receptacle Ratings for Various Size Circuits
Circuit Rating (Amperes) Receptacle Rating (Amperes)
15 Not over 15
20 15 or 20
30 30
40 40 or 50
50 50
So while 210.24 Table clearly engages the allowance of a minimun TAP onto the branch circuit…of 14A for the example you have given…in my opinion because the example states a tap from a 20A Receptacle Circuit and that is the potential load served…it would not comply to 210.19(A)(4) exception C
But again…thats me…lol…
As for if it is ok for the 20A to feed the tap to the 15A rated receptacle…I would disagree as it is still on a 20A circuit…which was not the posters original question…but I understand where you went with it…but the flaw is in the fact the circuit is rated at 20A…and I have a problem with that part…feel it should protect that outlet at the full OCPD rating of the weakest link…what happens if someone plugs in a 18-20+A load in the end device that is only rated for 15A and only has 14AWG conductors rated for the 15A attached…and the wire from it to the first receptacle that is 20A rated…it in my opinion would exceed the tap conductors rating.
Now…if you can guarantee the receptacle being added will not exceed the rating of the 15 A device…some could argue but in this case I believe you would not be able to determine that…unless it was a fixed known amperage…and I still would not like it and would FAIL it because point blank…it is a Receptacle and not allowed !
Dang…now that gets confusing just in the translation…lol
Personally…the majority of electricians if they tap off a 20A Circuit onto a 15A device and /or conductor…would want to protect the entire circuit at the weakest link…which would be a 15A OCPD.
While the article says it shall not be smaller than 14AWG…it still says it must be sized for the loads served…and WHO KNOWS what the loads will be so I just dont like it…others may disagree…safety wise I like that smaller conductor ( because who knows how long it might be… ) should be the protected link in the chain…your turn…
BTW…to everyone reading…I could have just said NO…it is not allowed as it violates 210.19(A)(4) Exception 1©…because the question was based on a Receptacle…
But you all know I am long winded anyway so…their ya go…lol
Thomas…no comment from ya fella…is that not the information you wanted?
Oh I don’t pig tail, smaller than the size of the circuit. So I don’t need convincing, but nice to have a little more info to help another electrician wire correctly. I had to go digging up an article. It addressed why people who are are running, 12# wire, some how find time to scrounge up 14# to pig tail. Seemed counterintuitive. The article seemed to give the motive is that you can’t back-stab with 12# [any more]. So to save time, the electricians in question, keep 14# with them to not use the terminals.
Bad workmanship? I think the answer is obvious. 
tom
Question
One of the #12 runs to the kitchen of the home had a legal junction box just inside the attic hatch with a 3 foot run to an attic light with #14 wire feeding a 60 watt bulb. Installed safety light in the attic for the new AC unit but did not down graded the kitchen ckt to 15 amps??
15 amp probably would be ok for most kitchen loads –
So do we report something that sticks out like a sore thumb that anyone can see or go on to bigger and better things?
Issue could be corrected by installing a socket and plugging in a light into it – replacing the 3 feet of #14 with #12 - just removing the light and taking that as a report issue (missing light)
Remember that all the wiring inside a range is #14 or less and we put breakers in rated at 50 amps and some of the ranges are hard wired not plug in
I love the NEC – somewhere the have a rule - too bad it is so hard to find
How about this one #12 feeding a 15 amp GFCI and breaker combo and #14 for all the down stream outlets — 20 amp main breaker
And home owner says to me when ask about any problem with anything electrical that after a major remodel one of the new kitchen ckts was shorted and would trip the breaker right away. After resetting it a few times there was a pop in a wall as per his wife and the problem went away – everything works ok now. – Drywall is all new with new paint etc. Why were they so honest??? (Drywall screw in cable SOMEWHERE is now a little short)
Are we all having fun??
rlb
(As per seller verbal disclosure during inspection pop in wall etc. No problem noted at inspection time.) Recommend dry wall company remove all screws and check for burnt ends - Recommend electrician install metal guard plates over wiring. recommend painter repaint all re-remolded walls Why me
RLB,
I hear ya brother…we run into alot of older homes that probably have a 20A kitchen circuit ( if lucky ) and many people tap onto the counter circuit…just part of the DIY mentality and in most cases hard for the HI to diagnose without it being obvious…if it is obvious i call it out as you said it could be fixed…or atleast have its safety increased.
I just would like to GRAB the whole world and EDUCATE them as they just do not know what they do…people think hey electricity will flow on any conductor and add things at will…and wonder WHY their are so many house fires in the world today…such a shame.
In your case of the kitchen…The real problem is the NEC clearly states the kitchen circuits must be 20A…and while the tap is done with 14 AWG…if it was only that light…and fixed then it may not be a problem in the eyes of the NEC…but I do like the idea of them dropping it down to a 15 A breaker…fixing the better of TWO evils is safer…
And it takes a great HI like yourself and the others here to notice those things…i for one THANK you for all you guys do…