Shower 8.5 on a 40mcb is it dangerous

[chrismoy1]

Hi guys

My tenant just had an electrician in to connect her cooker and has told her that the shower is dangerous and not to use it because it has a 40 mcb in the consumer unit and it should be a 32.
The cable is 6mm and the shower is 8.5kw.

Can you advise me please
Thank you in anticipation

 

[chrismoy1]

One things for sure they should be greatful they have got a landlord that cares, the fact you are investigating there concerns rather than just saying hey it works what u complaining about shows you care not to mention new cooker

I have since found out from the tenant that he did not even go upstairs to look at the shower so has no idea about it's power rating.
What is even more worrying he said that instead of connecting the cooker with 6mm cable he should really be using flexible multi strand cable like on her kettle or halogen cooker.
I have never heard of this can anyone please enlighten me.

Regards Chris

 

[chrismoy1]

One things for sure they should be greatful they have got a landlord that cares, the fact you are investigating there concerns rather than just saying hey it works what u complaining about shows you care not to mention new cooker

I have since found out from the tenant that he did not even go upstairs to look at the shower so has no idea about it's power rating.
What is even more worrying he said that instead of connecting the cooker with 6mm cable he should really using flexible multi strand cable like on her kettle or halogen cooker.
I have never heard of this can anyone please enlighten me.

Doing some calculations, I don’t agree with your tenants electrician. A 6mm cable, clipped direct will be absolutely fine on a 40amp mcb. The only issue is if the shower circuit is not on an RCD. Providing the run isn't miles and miles.
Putting a 32amp mcb in the circuit will just cause annoying tripping as the 8.5 kw shower will draw around 36amps.
Sounds like the electrician needs to look at the books a bit

Regards Chris

 

[chrismoy1]

Doing some calculations, I don’t agree with your tenants electrician. A 6mm cable, clipped direct will be absolutely fine on a 40amp mcb. The only issue is if the shower circuit is not on an RCD. Providing the run isn't miles and miles.
Putting a 32amp mcb in the circuit will just cause annoying tripping as the 8.5 kw shower will draw around 36amps.
Sounds like the electrician needs to look at the books a bit

The length of the run is 8 metres and there is a 30ma rcd in the consumer unit
I have since found out from the tenant that he did not even go upstairs to look at the shower so has no idea about it's power rating.
What is even more worrying he said that instead of connecting the cooker with 6mm cable he should really be using flexible multi strand cable like on her kettle or halogen cooker.
I have never heard of this can anyone please enlighten me.

Regards Chris

 

[Wilko]

Hi Chris - site unseen that doesn't sound like something an Electrician would say as an 8.5kW shower is not normally connected by flex. Certainly not a kettle flex as they will be rated about 3kW max.

 

[dmxtothemax]

Your electrician is absolutly wrong
8500w @ 240v = 35.4A
or even
8500w @ 230v = 36.9A
so 32A is not sufficent.
40A would be minimum.
What electrician in his right mind would hook up a water heater
without knowing for sure it's ratings ?
Scheer madness.

 

[Midwest]

Think the OP said his electrician said the ‘cooker’ should be connected with flexible cable?

I think your electrician, might be referring to the final connection between the house fixed wiring (cooker outlet plate) and cooker appliances. Some manufacturers provide specific leads, some electricians will use a suitably sized heat proof etc cable, but in some cases, a twin & earth cable would suffice. Most cooking appliance are fixed into position and are hardly ever moved. For comparison, a commercial oven, would need a suitable flexible cable, as it would be moved regularly for cleaning. Well most good kitchens would be cleaning behind it!

 

[davesparks]

I have since found out from the tenant that he did not even go upstairs to look at the shower so has no idea about it's power rating.
What is even more worrying he said that instead of connecting the cooker with 6mm cable he should really be using flexible multi strand cable like on her kettle or halogen cooker.
I have never heard of this can anyone please enlighten me.

Regards Chris

He could have used 6mm flexible cable or 6mm T&E cable, assuming that 6mm is the correct size. Either is perfectly acceptable as long as it is correctly installed.

I think this electrician needs to brush up on their knowledge of the regulations!

 

[telectrix]

He could have used 6mm flexible cable or 6mm T&E cable, assuming that 6mm is the correct size. Either is perfectly acceptable as long as it is correctly installed.

I think this electrician needs to brush up on their knowledge of the regulations!

and maybe retrain as a plumber. they ain't got a clue about electrics anyway, so he should feel at home.

 

[chrismoy1]

and maybe retrain as a plumber. they ain't got a clue about electrics anyway, so he should feel at home.

He also said that the 40 mcb for the cooker should be changed to a 32. As I understand it the principal of diversity could be applied so that could be ok but would a 40 mcb with a 6mm cable over a 7 or 8 metre run be dangerous clipped direct not in insulation?
It is just a standard cooker grill, oven and 4 rings.

 

[telectrix]

nothing wrong with 40A MCB on cooker. the guy's an idiot.

 

[chrismoy1]

nothing wrong with 40A MCB on cooker. the guy's an idiot.

Thanks for everybody's replies I think the obvious thing is for the tenant to get another electrician.

 

[davesparks]

He also said that the 40 mcb for the cooker should be changed to a 32. As I understand it the principal of diversity could be applied so that could be ok but would a 40 mcb with a 6mm cable over a 7 or 8 metre run be dangerous clipped direct not in insulation?
It is just a standard cooker grill, oven and 4 rings.

My gut reaction is that this person is trying to create extra work for themselves by scaring the tenant.

 

[chrismoy1]

My gut reaction is that this person is trying to create extra work for themselves by scaring the tenant.

I think you could be right about scaring the tenant as the things he has said do not make sense to me or a lot of other people.

 

[davesparks]

I think you could be right about scaring the tenant as the things he has said do not make sense to me or a lot of other people.

I'd ask him to prove his statements or else you'll make a complaint to trading standards about his cowboy tactics

 

[Blissof89]

Tell him to have a look in Appendix F of his on site guide and get back to you.

Is this guy definitely and electrician and not just an appliance installation guy from a electrical appliance retailer?