mortgage retention advice for current installation upgrade

[walkthenrun]

Hi guys,
i need to carry some work out to get my house to pass its mortgage retention, i had a mate from napit come round and do a electrical installation inspection condition report, as one of the retention on my mortgage is due to the old electrical installation. at the moment there is a 15 way merlin gerin consumer unit. I have identified all the circuit apart from one 15A breaker. anyway i was hoping to change the current unit to rcbo's i think this is probably the best thing at the moment considering the size of the house so if anything does go rong i can localise the problem more easily. guys i have come for advice as i dont know which unit to buy? am i doing the right thing by going for rcbo's. i need something that will allow me have at least 13 different circuits. the only thing i have found upto now is a Wylex 11 way Consumer Unit Type NH1104 that i could put 11 circuits on. The immediate advice my friend give me was to condition report was to update the consumer unit so that the shower is rcd protected, the lights in the bathroom are ip65. the supply to the summer house and the pond shed is in swa cable. is it possible to just take the current consumer unit and swap it directly for an 11 way rcbo consumer unit. would everything carry on working as it is working perfectly now.
i have identified each circuit as follows
1. annexe consumer unit and outdoor floodlight consumer unit (60A) (10mm cable and 2.5mm)
2. cooker (50A) (6mm)
3. upstairs sockets (32A) with two fuse spurs in garage from ring final in above main bedroom (2.5mm)
4. downstairs sockets (32A) (2.5mm)
5. 15A?
6. 5A lights in boiler room (G), garage(G), utility(G),main bathroom(U), small blue room(U), hallway(U), pink room(U) and kids room(U) G-ground U-upstairs (1.5)
7. shower (50A) (6mm 8.5kw shower clipped direct to wall)
8. main bedroom (U) and ensuite lights (U) (5A) (1.5mm)
9. kitchen(G) dining room(G) sitting room (G) and toy room lights (G) (5A) (1.5mm)
10. boiler (5A) (1mm)
11. Pond shed hager consumer unit (60A) (10mm)
12. summer house volex consumer unit (60A) (10mm)

some pictures are included thanks
main consumer unit

main c.u and outdoor lighting c.u

pond c.u

summer house c.u

annexe c.u

thanks in advance for your immediate advice if any more pictures are required please let me know thanks

 

[DPG]

From these 2 queries, are you sure you are competent to be doing this? Just a question, not having a go. Daz

* "on rcbos too? and the bathroom lighting c.b. too (can i leave that as i was planning on fitting selv lighting in there anyway?"
* "can you tell me for RCBO do you need seperate nuetral bars like you do on an split twin rcd c.u"

 

[bartkusal]

Originally Posted by DPG
What's the second cable going in to that 1st breaker? Daz

it is a feed for the small consumer unit to the right of the main c.u, which is responsible for the ring, that feeds the outside floodlights

so 60A breaker protects 2.5mm2 cable? No good is there, stick in 16A or 20a breaker

 

[walkthenrun]

Have to put what power rating your shower is, in past posts & ive just missed it?? im having an off day...

8.5kw 7 meter away from c.u clipped direct to the wall up onto wooden beam into d.p

 

[walkthenrun]

From these 2 queries, are you sure you are competent to be doing this? Just a question, not having a go. Daz

* "on rcbos too? and the bathroom lighting c.b. too (can i leave that as i was planning on fitting selv lighting in there anyway?"
* "can you tell me for RCBO do you need seperate nuetral bars like you do on an split twin rcd c.u"

well the rcbo has its own n out so i guess the answer is no you dont (but come on we do all have moments and this is my second year doing electrical i am a formulation chemist by qualification

 

[Spoon]

8.5kw 7 meter away from c.u clipped direct to the wall up onto wooden beam into d.p

So why are you trying to fit a 50A or higher MCB/RCBO?

 

[Engineer54]

So why are you trying to fit a 50A or higher MCB/RCBO?

Yep, a 40A MCB will be more than adequate for that size of shower!!

 

[walkthenrun]

So why are you trying to fit a 50A or higher MCB/RCBO?

a 45A would be adequate for now but i would in the future like to upgrade the shower to a 10.5kw but if i was going to upgrade the lot now i would put a 10mm cable in and change the pull down d.p to a wall mounted one and also get the correct breaker from the initial installation

 

[walkthenrun]

So why are you trying to fit a 50A or higher MCB/RCBO?

6mm 47A clipped direct and then voltage drop wouldnt have an advers affect over that distance, so a 45A c.b would be acceptable
8500/230=36.96A so 37A maximum current flowing
on 10.5kw/230=45.65A
10mm cable clipped direct 2c0re 63A 3core is 57A

 

[Spoon]

I dont mean this in a sarcastic way, but what is the fascination with people wanting to get a bigger and bigger showers. What is wrong with a 8.5kw?

 

[Spoon]

6mm 47A clipped direct and then voltage drop wouldnt have an advers affect over that distance, so a 45A c.b would be acceptable

Until you want to upgrade your shower to 10.5kw.

 

[Engineer54]

I dont mean this in a sarcastic way, but what is the fascination with people wanting to get a bigger and bigger showers. What is wrong with a 8.5kw?

Why anyone would ever need a 10.5KW shower, i will never know!! I'm using a 4.2KW shower over here and it's more than just adequate for a good hot shower!!

 

[Spoon]

Why anyone would ever need a 10.5KW shower, i will never know!! I'm using a 4.2KW shower over here and it's more than just adequate for a good hot shower!!

Maybe they want to re-enact a scene from Rambo, when he is in the police station...

 

[Engineer54]

Bet they don't sell many 10.5KW showers in France, where it seems the average domestic supply is limited to 12KVA!! ...lol!! ....It's only the daft British that want to be one better than the Jones next door!!! lol!!

 

[Spoon]

OP: Id be more concerned about the 2.5mm cable going to MCB 1 (60A) for the outside lights than the shower cable.

 

[Engineer54]

OP: Id be more concerned about the 2.5mm cable going to MCB 1 (60A) for the outside lights than the shower cable.

That cable can be slipped into the downstairs lighting Breaker. Obviously installed by a DIY'er that one!! lol!!