MCB size and type required for a 10.8kW electric shower

Joined
10 Feb 2008
Messages
4
Reaction score
0
Location
Cardiff
Country
United Kingdom
I've replaced an old electric shower with a 10.8 kW shower.

However, I need to replace the current 30 Amp MCB with a higher rated MCB.

The installation guide specifies 45 Amp. However, the nearest match to this I can get for my consumer unit is 40 Amp and 50 Amp.

Should I purchase a 50 Amp MCB for this shower?

Would you recommend a Type B or a Type C for this electric shower?

Thanks in advance

Neil
 
Sponsored Links
There may be more to it than just upping the size of the MCB. Is the cable sufficiently rated for the additional load? You should also note that this work will be notifiable to your LABC under part P of the building regs.
Best bet imo is to employ the services of an electrician who is a member of a competent person scheme.
 
Hi Spark123

Thank you for your reply. The cable is 10mm which should be fine over a length of around 15 metres (in plastic ducting). For your interest, the circuit is also protected by a 30mA RCD within the consumer unit.

Thanks

Neil
 
Sponsored Links
Hi Spark123

Thank you for your reply. The cable is 10mm which should be fine over a length of around 15 metres (in plastic ducting)


yes, 10milli in trunking drops to 52A, so that's ok. But can your CU take the extra load?

Can you post a piccy of it?
 
Hi Securespark

Thanks for your reply. My consumer unit is rated at 100A.

The unit is an old Square D unit, probably from late 80s if it is the origional fit in the house.

The problem is that I think it is now obsolete, and I cannot seem to find a replacement MCB for it. The current shower MCB is a Square D QO-X (Instantaneous trip Type 4). However, I believe that the old QOE type can also be used in this unit which I can find at:

http://www.thefusecompany.com/fuse.php?cPath=54&products_id=696

hence my original questions of Current rating and type

If I can't source the correct replacement MCB, then I will call in a Type p electrician to either replace my consumer unit or put in a second dedicated consumer unit for my shower.

I would prefer to replace just the MCB if possible.

Thanks

Neil
 
Hi Ban all Sheds,

On closer inspection, it does appear to be 6mm cable as the earth is only single strand, so I will need to have the cable upgraded to 10mm. Luckily the cable is routed through plastic trunking, so it shouldn't be too big a job.

Thanks

Neil
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Back
Top