Receptacle on one breaker, light switch next to it on another breaker. Mistakenly touched receptacle black wire on light switch and caused sparks. Receptacle failed after that. Had another nearby GFCI receptacle STILL operating (dehumidifier operating entire time) that is on same breaker as fried receptacle. Turned off breaker (mistake in first place, thought receptacle and light switch were both on breaker). Breaker 20A, both plain receptacle and GFCI recep are 15A. Decided to go with 20A GFCI to replace fried receptacle. Installed and when turned on breaker NOTHING worked, including GFCI receptacle which does not reset and shows no light indicator. Do not know wire capacity (this was over fighting ants crawling through wall at receptacle). Switched Breaker back and forth and get NOTHING. Have decided to get obviously 15A receptacle to replace bad receptacle. Bought new breaker. Any thoughts? Have not seen charred wire and have not taken GFCI receptacle out for inspection.
It sounds like one of the wire connections is faulty. Problem is, it's not where you want it to be.
It's very common after an overload for a wire connection (where wire attaches to a device) to simply stop working. What has happened is that it was making a poor connection up til now (either because backstab connections were used, or it was under-torqued) and the surge of current burned it out entirely.
For any given wire, this could occur on either end of the wire. You don't know which. When you replaced the receptacle, that obviously re-seated that end of the wires. But the problem could be at the other end, which is presumably at another switch, recep, or wire nut that is also on that circuit.
It can also happen at "wire nuts" which aren't tight enough. People who don't tighten wire nuts enough usually use tape to keep them from just falling apart, so tape is a warning sign.
So it becomes a "bug hunt" trying to find it.