Cooked wall switch... Scary. Please come in...

[K-Man]

Switches can fail internally, as Wheel mentioned. It's common with old switches in older houses. When they fail, they either arc internally, causing overheating, or they short and keep the circuit on (so the light can't be turned off at the switch). A couple of years ago I replaced a nearly 100–year-old wall switch that failed so that the overhead light stayed on.

Newer switches can fail too. This could have been one. Even if manufacturing is 99.99% good, that still leaves that 0.01% that will fail prematurely.

 

[chexxers]

i might add thats a CHEAPO switch!!! search + learn about devices + of course proper sized ciruits + wiring is KEY!!! not an electrican BUT there are books as well as the net to TEACH US!!!

 

[JeffKeryk]

Thanks to everyone who contributed. Based on @Pablo and others advice, I am going to pigtail the switch so that it does not become overloaded.

And reconnect the wires so they come out the back!

 

[Pablo]

Sounds great but don’t forget to let the crowd know what else that circuit powers

 

[ka9mnx]

If you decide to pigtail, give the Wago 221 3-wire or 5-wire connectors a try. In my experience they are easier to use than wire nuts.

Not legal in some areas.

 

[wavinwayne]

Not legal in some areas.

Wow, where?

 

[factorytuned2012]

Not legal in some areas.

legal? they meet code. but maybe you mean jurisdictional.

 

[SammyChevelleTypeS3]

Amateur opinion is the wires not wrapped around the screws are causing a high resistance. Not enough surface area. The contact area the electricity is traveling across is just the tangent of the wire.

I would be inspecting every switch and outlet in the house after seeing that.

It sure makes you wonder what type work they did in other places.... sockets and other switches.

 

[ka9mnx]

legal? they meet code. but maybe you mean jurisdictional.

Correct...

 

[zzyzzx]

Everything was tight.

It looks poorly installed. You don't put two wires on one screw terminal like that. Plus they didn't bother to try to curve the wire around the screw. If you are too lazy to do that part right, use a spec grade where you can just push it in and use the provided screw down terminal, like this (except I would not leave so much exposed wire on the leads):

I am assuming that you can even get switches like that. The picture might be an outlet.

 

[alarmguy]

That is exactly what I am guessing over the interwebs. Someone put another outlet or load on the incoming power not the switched side. Bad connection high current load. Heat smoke smell

Yes, it looks like they used the switch itself to continue the load to other parts of the house.
The proper way would have been to use a wire nut on the line side (black wire) to tie in all three wires with one wire of those wires then going to power the light switch. Something isnt right. A light bulb, wouldnt have melted a wire like it did.

There is also one other thought on my mind however hands down I think the above is the reason.
The other possibility would be a lightening surge (nearby lightening strike) I certainly would check some other outlets and switches.

 

[Pablo]

Yes, it looks like they used the switch itself to continue the load to other parts of the house.
The proper way would have been to use wire nuts on the line side (black wire) to tie in all three wires with one wire powering the light switch.

This and the mystery continues as to what that load may be!

 

[JeffKeryk]

Yes, it looks like they used the switch itself to continue the load to other parts of the house.
The proper way would have been to use a wire nut on the line side (black wire) to tie in all three wires with one wire of those wires then going to power the light switch. Something isnt right. A light bulb, wouldnt have melted a wire like it did.

I will install a pigtail like you and @Pablo advised. My guess is something happened. And my other guess is I gotta check everything else.
All good AG. BITOG has my back!

 

[SammyChevelleTypeS3]

One never knows what you will find in any home or building we purchase unless you built it yourself.

 

[JeffKeryk]

One never knows what you will find in any home or building we purchase unless you built it yourself.

In my case, heaven forbid...

 

[SammyChevelleTypeS3]

In my case, heaven forbid...

Just this week we had the entire electrical system gone thru in our house of the past 25 years. Like an idiot , at the time we bought this one we were so ready to get out of the other house, I did not even have this one inspected. Kinda late now. But I had some worries about the electric system and wiring. We found one minor issue. Replaced all the breaker panel boxes outside and two fuse boxes inside with all new breakers. Some worn switches changed and installed several GFCI outlets. I can rest at ease now knowing that it is all new and checked out. Reason= house is about 60 years old.