What to do with a 20 amp fuse...

[redwin11]

I got home last night to find the lights had all gone out in the house - after much searching i finally found the fuse box and the fuse which had blown (see picture).

It looks extremely old but i assume all i need to do is replace the fuse wire and it should be fine again.

However, it says it's a 20A fuse and the electrical shops i've been to do not have it. They only have 5, 15 and 30.

I will try to hunt down some 20A wire, but in the meantime, shall i try 15A, seeing how it's just for my lights? Or is that a complete no-no in a 20A fuse?

Any advice appreciated!

 

[Clitheroe]

20 Amp is far too strong for a lighting circuit!
15 Amp would be still too strong!

Are you sure the fuse is only for the lights? If so, then there is something wrong.

 

[redwin11]

Hmm, well perhaps it does more than the lights, but at the moment everything else is working fine in the house aside from the lights.

We have three separate fuse boxes - one does the kitchen, one does the sitting room downstairs and the bedrooms upstairs and the other (as far as i could tell) does the lights.

We've lived in the house since June and have never had a problem until the fuse went last night, so i have no idea why it's 20A.

So i take it putting 15A wire on a 20A fuse is not an issue?

 

[JohnD]

If it's a lighting circuit it should be 5Amp fuse. Try it with 5A wire and see what happens. Also, fusewire is often supplied on a card with 5A, 15A and 30a wire - compare the thickness of the old wire with each to see which it seems to match.

If the fuse immediately blows, look for anything other than lighting that has been attached to the circuit, and disconnect it. The cables used for lighting circuits are not safe with heavy loads, so the blowing fuse may be saving you from overheating and fire.

I have some concerns for your safety:

Your rewirable fuses look very old, you have three separate fuseboxes; your lighting circuit was (possibly) fused at 20A (but, with rewirable fuses, you never know what size wire had been put in - maybe the label was wrong). These are all signs that you have an old and possibly unsatisfactory electrical installation.

I recommend you start asking friends and neighbours for a reliable local electrician, and ask him to take a look and give you an opinion (this may not take him long).

If you can take a few pics of the fuseboxes and the area around your meter (showing the cables coming in and going out) we may be able to say more.

 

[redwin11]

If it's a lighting circuit it should be 5Amp fuse. Try it with 5A wire and see what happens. Also, fusewire is often supplied on a card with 5A, 15A and 30a wire - compare the thickness of the old wire with each to see which it seems to match.

If the fuse immediately blows, look for anything other than lighting that has been attached to the circuit, and disconnect it. The cables used for lighting circuits are not safe with heavy loads, so the blowing fuse may be saving you from overheating and fire.

I have some concerns for your safety:

Your rewirable fuses look very old, you have three separate fuseboxes; your lighting circuit was (possibly) fused at 20A (but, with rewirable fuses, you never know what size wire had been put in - maybe the label was wrong). These are all signs that you have an old and possibly unsatisfactory electrical installation.

I recommend you start asking friends and neighbours for a reliable local electrician, and ask him to take a look and give you an opinion (this may not take him long).

If you can take a few pics of the fuseboxes and the area around your meter (showing the cables coming in and going out) we may be able to say more.

Right, i had a closer look at the fuse and the old wire on it is 5A - should have worked that out from the start! At least that's solved one problem.

One of the fuse boxes (kitchen) is newer than the other two, but presumably we'd want to be working off one fuse box? What are we talking for that sort of job, £100 or so?

 

[JohnD]

Sadly there is a lot of testing that has to be done (and quite likely rectification of old and unsatisfactory wiring) so will be more than that.

It is notifiable under Building Regulations and the easiest way is to have it done by an electrician who is a member of a self-certification scheme and authorised to perform the test and certification. Otherwise you have to submit plans to the council and pay them for inspection and test.

BTW check all your other fuse labels and correct them.

 

[redwin11]

Sounds a nightmare, but needs doing, i suppose.
Thanks for the advice!

(Also you can use the "reply" button not the "quote" button.)

But I like using the quote button...

 

[dingbat]

One of the fuse boxes (kitchen) is newer than the other two, but presumably we'd want to be working off one fuse box? What are we talking for that sort of job, £100 or so?

Ooh, I love a good laugh, me.

 

[securespark]

For the materials, maybe...

 

[breezer]

For the materials, maybe...

that cant be right, there is a lady on th radio that says the materials are only £6.99 / metre

(Thought) you probably don't listen to the same radio station as i do