Return of the Plumber.....

[kentster]

Just got a call from my sister who had a new bathroom (and 10.5kW shower) fitted 4 weeks ago because their cartridge fuse has just blown. She proceeds with the "i've popped down B&Q" to get a replacement fuse, all very well and good, until she tells me its a 30A fuse!!!

Suggested she got hold of the sparky who fitted the shower and confirm why its on a 30A and whether the cable size, installation method allows for a bigger fuse, to then be told the plumber advised he didn't need to get a sparky in as he's replacing like for like.

So my questions: -

1) I'm assuming like for like in regards to showers means the same wattage?
2) Regardless of above should there have been a minor works cert?
3) 10,500 / 230 comes out at 45.65A so technically that means a 50A fuse, but in the real world would you use a 45A?
4) When looking in the BRB at current carrying capacities of cables do you guys use the 30 degree figures or use correction factor down to something lower?

 

[garyinderby]

I think the short courses are a starting point. The trick is to know this and when starting out not bite off more than you can chew. I took the short course as a career change, though i found it to be common sense in the most part. The electrical content was very intense and contary to common belief not everyone passes.
there is also a big difference in the attitude to the sales talk at the learning centres, you are left in no doubt that you are learning the basics. I for one am grateful to have been able to do the course and would also like to thank all the members of this forum for there time, patience and considerable knowledge they share with us guys that didnt come into the trade by the traditional route. there will always be muppets out there but if the good guys stand together(regardles of how we came to be electricians) we can beat the cowboys into submission. Gary

 

[Octopus]

Out of interest what was the rating in the shower which was taken out? I can't believe that there was a 10.5KW shower in place before!

 

[kentster]

Hi Murdoch, the original shower was a 7.5kW we think, so wasn't like for like....! There's also no RCD protection and i'm pretty sure once someone has looked at it, that the cable will be 6mm.

Can already feel the argument starting when the plumber is called back out to pay for all the tiles to be removed so a new cable can be run in ;-)

 

[Octopus]

I think the cost to the plumber will be more than lifting a few tiles - surely it can't be that simple. At the very least somebodies got to pay for the new circuit breaker and then with about RCD protection.

I fear your sister is going to have to pay some of it.

Maybe there's a friendly sparky in Bournemouth who can nip round before you get the plumber back so she's clear on what is required!

Good luck

 

[kentster]

Yeah good point, if only it were that simple as i'd have liked to be there when the sparky popped round so I could learn, but she's over the border in Wales - little bit far to travel.

 

[Amp David]

Still stick by my first post regarding what action needs to be taken!

 

[EoinConway]

Still stick by my first post regarding what action needs to be taken!

I agree, kick him in the head

 

[pushrod]

This is exactly why part p fails, cos if you look at part p it is actually not notifiable to replace a shower like for like, problem here is that your plumber assumes one shower is the same as another, and has disregarded the wattages. Aswell as the fuse, i would be checking what size the cable that was supplying the old shower is, if it is 6 mm it will be grossly undersized for a 10.5kw shower

It might be undersized when you take the installation method into account but 6mm clipped direct is actually 47A, which is larger than the Ib in this case