Urgent advice reqd!

mk1vanman · Jun 23, 2009

hello there! first post! Well here i go, basically i have a spark in my house doing work for the plumbing company i have in fitting a new en suite for me, the house has an old style consumer unit, not rcd protected, but has one of these little rcd units for a shower that was put in by the previous owner, think its a 40amp breaker!? anyway, this spark plans to add another of these units for the new shower in the en suite, dont know why but somthing tells me this isnt right!? i could be wrong as i am no spark! ive had a look at where the tails are and where they go in, the out going tails for this little rcd shower unit leave which is fine, but surley there isnt room for yet another set of cables for the new shower breaker??
Please forgive if my terminology isnt great ive tried to describe it as best as i possibly can, really hoope the response will be "dont worry it sounds ok" but somthing just dosent sound correct here!!

any help/advice would be great folks! thank you!

mags1972 · Jun 24, 2009

mk1vanman said:
yes i thinkso, his tails for this little rcd unit for the shower are not connected into the CU at all, they are into the bit where the main tails come in! so this isnt correct now??

What are the the odds that the main fuse is 60A!!!!

The best way under your current setup would be to take a 6 or 10mm feed from a 40A fuse/MCB in the main Cu to the shower units, thats assumiong you had 2 spare ways. The main problem here is I'm assuming your main CU is full which is why this hasn't been done, and 2 electric showers plus your existing circuits will be probably more than your main fuse is rated at, however there is a wonderful thing known as diversity and the chance of all the circuits being full load at the same time aren't good so the fuse probably won't blow, this doesn't make it right though.
I know I'm sounding like a broken record but a new CU is the way to go. Not sure if its an old rewirable wylex CU you have but if it is then they need replacing anyway they should be illegal now!!

lister · Jun 24, 2009

can we have photos pleeeeeeease

then we can tell you one way or the other.

Mr Mark Sparks · Jun 24, 2009

Quote:
Originally Posted by Moog

Are you saying he has the new shower connected before the CU? If this is the case and your whole installation exceeds the rating on the suppliers protection device then you will be paying out each time the suppliers fuse blows around £50 a time

yes i thinkso, his tails for this little rcd unit for the shower are not connected into the CU at all, they are into the bit where the main tails come in! so this isnt correct now??

dont worry this post by moog is a little misleading
the overall load on the suppliers fuse is the same no matter how or where the shower is connected
as said by most a new cu is ideal but what he is doing seems ok

mk1vanman · Jun 24, 2009

Mr Mark Sparks said:
Quote:
Originally Posted by Moog
Are you saying he has the new shower connected before the CU? If this is the case and your whole installation exceeds the rating on the suppliers protection device then you will be paying out each time the suppliers fuse blows around £50 a time

yes i thinkso, his tails for this little rcd unit for the shower are not connected into the CU at all, they are into the bit where the main tails come in! so this isnt correct now??

dont worry this post by moog is a little misleading
the overall load on the suppliers fuse is the same no matter how or where the shower is connected
as said by most a new cu is ideal but what he is doing seems ok