Wall socket overheating Plug casing caught fire.

[lozzy73]

Hi

I don't know if the reason for this is faulty wiring in the wall socket or faulty wiring in the extension lead plug that caught fire.

Basically, I had a normal extension lead (off which was running laptop, 2 heaters (1.2 kw each) and a lamp). For a couple of days I could smell TCP and had a look around but couldn't find the cause. Last night however, I only knew there was a problem when the lights flickered and electricty stopped and there was a puff of smoke coming from the wall socket from behind the sofa.

Switched off the electrics from the fuse box and pulled out the very hot plug (with oven gloves). The wall socket was burning hot. However there is still one of the pins of the plug stuck in the socket in the wall.

This tells me that there was faulty wiring in the plug itself but I can't understand why the wall socket was so hot. Also can't understand why fuses in the plug/fuse box didn't blow before this little fire broke out. The plug has massive hole in it where the plastic has melted and is missing one pin which is still stuck in the socket on the wall.

Obviously I overloaded the extension lead last night (don't normally have two heaters running) but can't understand why no fuses blew before.

Anyone have any ideas?

Thanks

 

[ban-all-sheds]

Switched off the electrics from the fuse box and pulled out the very hot plug (with oven gloves). The wall socket was burning hot. However there is still one of the pins of the plug stuck in the socket in the wall.

The socket will need replacing asap, you shouldn't turn that circuit back on until this has been done and the cables supplying it checked for damage.

This tells me that there was faulty wiring in the plug itself

Probably.

but I can't understand why the wall socket was so hot.

Because brass is a very good conductor of heat.

Also can't understand why fuses in the plug/fuse box didn't blow before this little fire broke out.

Because it was caused by a poor connection. High resistance = heating up. Until/unless you get a fault (i.e. short circuit) caused when insulation melts and L & N or L & E touch the current flowing will not be too high.

Obviously I overloaded the extension lead last night (don't normally have two heaters running) but can't understand why no fuses blew before.

laptop, 2 heaters (1.2 kw each) and a lamp).

That's going to be less than 3kW, i.e. less than 13A.

3kW is more than enough to start a fire, nowhere near enough to blow a fuse.

 

[lozzy73]

Ok thanks.

All my electrics (lights and power) are on main fuse (old wiring and old fuse box).

I don't intend using that socket until it is replaced and checked as you say but am I safe to use the others? Everything seems ok to me but I'm not sure if they are on a ring circuit (as the lights are).

Funny thing was, the cat kept running behind the sofa all day yesterday and I couldn't work out why. Obviously she could smell something odd.

 

[SUNRAY]

Hi

I don't know if the reason for this is faulty wiring in the wall socket or faulty wiring in the extension lead plug that caught fire.

Basically, I had a normal extension lead (off which was running laptop, 2 heaters (1.2 kw each) and a lamp). For a couple of days I could smell TCP and had a look around but couldn't find the cause. Last night however, I only knew there was a problem when the lights flickered and electricty stopped and there was a puff of smoke coming from the wall socket from behind the sofa.

Switched off the electrics from the fuse box and pulled out the very hot plug (with oven gloves). The wall socket was burning hot. However there is still one of the pins of the plug stuck in the socket in the wall.

This tells me that there was faulty wiring in the plug itself but I can't understand why the wall socket was so hot. Also can't understand why fuses in the plug/fuse box didn't blow before this little fire broke out. The plug has massive hole in it where the plastic has melted and is missing one pin which is still stuck in the socket on the wall.

Obviously I overloaded the extension lead last night (don't normally have two heaters running) but can't understand why no fuses blew before.

Anyone have any ideas?

Thanks

Probably another case of a 13A plug not being fit for purpose.
Which pin came out?
My money is on the live.

 

[SUNRAY]

Ok thanks.

All my electrics (lights and power) are on main fuse (old wiring and old fuse box).

I don't intend using that socket until it is replaced and checked as you say but am I safe to use the others? Everything seems ok to me but I'm not sure if they are on a ring circuit (as the lights are).

Funny thing was, the cat kept running behind the sofa all day yesterday and I couldn't work out why. Obviously she could smell something odd.

Probably sitting on the warmth.

 

[lozzy73]

Yes, it was the Live.

It's a Volex extension lead. Have had it for years, always been ok.

I just wasn't sure if it was caused by faulty wiring in the socket itself (hence my question that I couldn't understand why the socket was so hot).

 

[DetlefSchmitz]

The plug's fuseholder was probably badly made so that the fuse didn't make proper contact. The socket would be hot because the live pin conducted the heat into it.

The danger is that the heat might have damaged the fixed wiring to the socket, and if you use other sockets in the place, the current will have to flow through the damaged wiring. So it would be better not to use the whole circuit till the socket is replaced and the wiring to it checked.

 

[lozzy73]

Have added some pics.

//www.diynot.com/network/lozzy73/albums

 

[lozzy73]

The plug's fuseholder was probably badly made so that the fuse didn't make proper contact. The socket would be hot because the live pin conducted the heat into it.

The danger is that the heat might have damaged the fixed wiring to the socket, and if you use other sockets in the place, the current will have to flow through the damaged wiring. So it would be better not to use the whole circuit till the socket is replaced and the wiring to it checked.

Ok thanks, that's what I was worried about. I thought it was a bit odd when the lights flickered last night. The lights are on a ring circuit so I should imagine the power is as well and the lights and power share one fuse. I'll get someone out to check today.

 

[stillp]

Could equally well have been a loose connection in the socket wiring and the plug just happened to be more sensitive to the excess heat. Either way, the socket will have been damaged and therefore will need replacing.

 

[SUNRAY]

Have added some pics.

//www.diynot.com/network/lozzy73/albums[/QUOTE]

Yes quite a normal thing to happen and demonstrates the need for regular inpsections.

AS has been said the socket must be changed.

 

[ban-all-sheds]

I don't intend using that socket until it is replaced and checked as you say but am I safe to use the others?

Not necessarily. I would strongly advise against it.

Everything seems ok to me but I'm not sure if they are on a ring circuit (as the lights are).

They probably are (what's the fuse rating?).

The lights almost certainly won't be.

The lights are on a ring circuit

Almost certainly not.

the lights and power share one fuse.

They'd better not....

 

[lozzy73]

The lights ARE on a ring circuit. I live in a flat - the wiring is 40 years old - black and red.

The lights and power share ONE fuse switch in the cupboard whether or not there are two fuses behind I'm not sure but when the plug fizzed and smoked last night, the lights went on and off.

 

[ban-all-sheds]

The lights ARE on a ring circuit.

How do you know?

Have you done all of the testing of the circuit you'd need to verify that it is a ring?

I live in a flat - the wiring is 40 years old - black and red.

It's never been common practice to use rings for domestic lighting circuits - not now, and not 40 years ago.

The lights and power share ONE fuse switch in the cupboard whether or not there are two fuses behind I'm not sure

I see what you mean. There will be two.

Hopefully.

but when the plug fizzed and smoked last night, the lights went on and off.

You should get that checked out too.

Do you own the flat, or rent it?

 

[lozzy73]

The lights ARE on a ring circuit.

How do you know?

Have you done all of the testing of the circuit you'd need to verify that it is a ring?

I had new light fittings installed a couple of years ago. The engineer confirmed it was a ring circuit then - through each fitting is an additional live connecting it to the light in the next room. He actually muddled them at one point so that switching the light on in the bedroom actually switched the light on in the lounge. This is what I understand to be a ring circuit. He said he'd never come across it before.

I live in a flat - the wiring is 40 years old - black and red.

It's never been common practice to use rings for domestic lighting circuits - not now, and not 40 years ago.

See above

The lights and power share ONE fuse switch in the cupboard whether or not there are two fuses behind I'm not sure

I see what you mean. There will be two.

Hopefully.

I think there are from memory - these are the big old Wilex fuses

but when the plug fizzed and smoked last night, the lights went on and off.

You should get that checked out too.

Do you own the flat, or rent it?