fused spurs

[Dotty]

Lol, had the balls to admit though! don't see that on an electrical forum ;-)

Ach. I'll always admit when I'm wrong. Don't happen often thankfully!

 

[stratplus]

the boiler going in the airing cupboard?

No, boiler in kitchen downstairs.

 

[stratplus]

Flex is used because of the fact the front control panel is made to move for access, flat t&e is used for fixed wiring, and I can't remember pyro being used for anything that could move.

So if you were to install a seperate room stat (programmer built into boiler) you would have to run another flex all the way to the stat from the boiler. So that will be two flexes, one from the fcu to the boiler and another from the boiler to the stat. How do you size the cable to the stat I this scenario?

 

[ShaunCorbs]

So if you were to install a seperate room stat (programmer built into boiler) you would have to run another flex all the way to the stat from the boiler. So that will be two flexes, one from the fcu to the boiler and another from the boiler to the stat. How do you size the cable to the stat I this scenario?

get a sparky in simple

 

[stani]

I wouldn't run a flex that sort of distance, in this case I would use 1.5mm flat t&e from the stat to a connection unit at the side of the boiler and then a flex from connection unit to boiler, again I would use 0.75mm flex.

 

[ShaunCorbs]

I wouldn't run a flex that sort of distance, in this case I would use 1.5mm flat t&e from the stat to a connection unit at the side of the boiler and then a flex from connection unit to boiler, again I would use 0.75mm flex.

you missed a point

 

[newcastle phill]

I wouldnt run flex in a wall.
Its called flex for a reason.
Over any distance and if wiring concealed or burried -TaE - simple

Or bloody wireless lol

 

[stratplus]

Lol, been an interesting discussion over eight pages! Thanks guys for your input.
Asked a number of sparkys on site similar question about running flat t+e into the boiler and all have said it would be fine and couldn't give a reason not to. Always good to hear multipal opinions.

 

[MOSSEP]

Although I would also use flex, the use of t+e cabling directly into the boiler is not going to cause any issues. The operating temperature rating of standard t+e is 70 degrees and with considered cable routing it is unlikely to touch any pipe that would exceed that. With regard to the flexibility, although its meant for fixed wiring, I don't think that a boiler covers is moved often enough in its lifetime to deteriorate the cable in any way. The only thing likely to cause the sheathing of the cable to crack is exposure to UV rays, and thats probably not possible inside a boiler :smile:

 

[spanner]

That was why I asked the question. 2.5mm from the board on a 15amp 3036 rewireable fuse to the immersion. Then a 1.5mm from the spur to the boiler with a 3 amp fuse at the spur. Just thought the 15amp at the board should be changed to a 6amp. Wasn't sure with the 2.5mm t+e.

Sounds fine to me providing the run is going to a 3amp fused spud outlets for first, and it's all 230v. @3amp you could split / chockoff the lighting ring .

 

[Nostrum]

Sounds fine to me providing the run is going to a 3amp fused spud outlets for first, and it's all 230v. @3amp you could split / chockoff the lighting ring .

Not good practice when it's labelled lighting on the CU!

There is nothing to stop you regulatory wise wiring your whole house in flex if you wish.

 

[spanner]

Not good practice when it's labelled lighting on the CU!

There is nothing to stop you regulatory wise wiring your whole house in flex if you wish.

Sure. But you could have even used a 45amp outlet providing you regulate the source @ that minimum power output..!!

 

[cr0ft]

Well having just spent £96 to be enlightened by BS 7671:2008 Amendment 3 this weekend I will let you know the definitive answer to this fused spur milarky once I read the updates.

ZZZZ

 

[stani]

Did you get the OSG with that

 

[spanner]

Did you get the OSG with that

What's an OSG?

 

[stani]

On site guide

 

[ShaunCorbs]

What's an OSG?

elecs book like our viper book

 

[spanner]

On site guide

Thanks.!

 

[cr0ft]

Did you get the OSG with that

Yes mate.

 

[cr0ft]

There was an argument going on earlier on this thread about whether or not you could use a fused spur on a 2.5mm T&E radial circuit protected by a 16a or 20a breaker. Pg 454 of the new regs book (yellow one) shows the 2.5mm radial circuit without any fused spurs on it. It shows a 4mm radial circuit with fused spurs on it to protect a smaller cable running of it (the circuit is protected by a 32A MCB).

It's not actually explicitly ruled out in the regulations book as far as I can see. The OSG is of course an abridged version of the regs book.

As usual, lots of ambiguity for the money I've spent!!

 

[stratplus]

When I said fused spur I should have said fused connection unit. Effectively from board 16mm rewireable fuse 2.5mm t+e to a fused connection unit. Then 1.5mm t+e from the fcu to boiler. Ideally that part should have been flex.