c/u change couple of questions

[crow11]

hi all, if youre doing a c/u change and you do a survey first and the kitchen is a old single storey extension, with no accsess at all to the roof space but there a 4 downlightlers which when you remove you can see insulation but can't see proper to work out the depth would you apply method 101 to be on the safe side, problem being there is a 6mm cooker cable there and method 101 would take the cable to 27A meaning mcb would have to be 20A,checked cooker and its only 2.2kw (9.6A) so 20A mcb is no probs but the cooker switch as a plug outlet which according to the regs on diversity is to add 5A still within the limits but just concerned if say they bought a 3kw kettle and used it in the cooker socket and have cooker on full and make a brew it is going to be drawing more than 20A and obviousy trip,but if i was to use method 100 then a 32A mcb could be used, would you always use the higher method with the lower A rating to be safe,


next question each ceiling rose as only 1 t&e coming into it,normal j/b under floorboards,would all these have to be changed to m/f j/bs before you could do the c/u as they do not comply with the regs as they are cheers

 

[jaydee81]

hi even if you did have cooker on full and 3kw kettle plugged in to socket total loading would be about 22 amps which isnt enough to trip 20 amp mcb would just note jb issue on installation certificate and leave it alone

 

[SPARTYKUS]

Agreed ^^^. don't worry. Kettles only on a few minutes!

 

[telectrix]

agree with above posts. as for the JBs, as long as your readings for the circuit are good, then it's OK to leave them as they complied when they were fitted.

 

[crow11]

new problem regarding my first post, kitchen ring main also runs above ceiling was previously on a 32A, the problem is i am not going to energize the kitchen ring at the moment due to the fact i dont know how much insulation is up there, the house is empty at the moment so explained this to client and he is in agreement, he as arranged for his builder to come in and put a hatch in so i have access to roof space i have my elecsa asessement this saturday and builder can't get there till next week, would you think the best option would be to leave the kitchen ring disconnected and explain to the asessor why i have left it disconnected until i find out what is above, i will energize it so i can do my live tesing then disconnect it again afterwards as there are no loads on it at the present time so i can fill out the eicr would this be the best option.

just out of interest i cant find anything anywhere in the regs to say what the max ccc is for a 2.5 ring is it just double of a 2.5 so it would be 54A max sorry if this is a silly question cheers

 

[ashrow]

I personally think you are worrying to much
Existing JB are of no concern if all readings at time of test are ok (you could but a comment on the cert to say you suspect JBs but there is not access)
If there is no access to that roof void i doubt the insulation is more then 50 mm

 

[crow11]

cheers for the reply ashrow i know i am worrying to much just with it being my first asessment lol, just dont want him to turn round and say why you put it on 32A when i don't know what reference method it is

 

[Garythenab]

Your definately worrying too much. All you are responsible for is the board change. As long as your not connecting anything dangerous or silly back e.g broken ring then you will be fine

 

[Garythenab]

I done a Cu change for my Elecsa assessment. It's not new wiring which is what u expect with a board change IMO