Two RFC merged in to one?

[pc1966]

Helping out a friend and a CU change is really the best option as sockets in kitchen and downstairs room not on RCD protection. Now one of the WTF moments is it appears (not fully checked yet) that one small room with 2, maybe 3 sockets at most, has a separate RFC from the kitchen. In turn other downstairs rooms are on a different RFC. Kitchen also has a 16A radial for a couple of sockets. Yes...odd design.

• Simple and obvious thing is to put back both RFC as currently done.
• Part of me thinks it might be as well making them in to a single RFC by linking ends of each at the CU then remaining ends are a single RFC.

So just wondering what folks on here would think about a pointlessly small RFC in a house with 4 other RFC and a radial.

TL;DR would you merge RFC?

 

[timhoward]

Would merging them make the general division of the installation more coherent, i.e. simpler to label the consumer unit?

 

[pc1966]

It would be slightly simpler, in that the two 'additions' to the original house (this room seems to have been a small shop next door, kitchen is a modern extension at the rear) as one circuit.

It would also make the overall demand look more sane, just now it has the following in the main CU:

• 1 * 63A sub-main to 2nd CU
• 2 * 40A for cooker & hob
• 2 * 32A RFCs
• 1 * 16A radial
• 2 * 6A lights

So your standard estimate of max demand is 130A off a (I guess) 100A fuse. Which is nonsense as none of those circuits are likely to run anywhere near full capacity.

Neither cooker or hob need to be 40A, so am planning to drop them to 32A. Same for lights, no need for two as they also serve the same small areas (rest of house lights on 2nd CU's 4*6A RCBOs) and simpler to merge in to one RCBO. Merging RFC makes some sense are total room + kitchen areas is not great, I can check but doubt it is over 50m^2.

Ironically the 16A radial is labelled "socket under sink" but that seems (still to check for sure) now to have the majority of current-hungry appliances on it!

 

[Pretty Mouth]

I think either way is fine. I don't think it's necessary to merge the small ring with the kitchen one, but at the same time can see no harm in it. It's your call!

 

[mainline]

Helping out a friend and a CU change is really the best option as sockets in kitchen and downstairs room not on RCD protection. Now one of the WTF moments is it appears (not fully checked yet) that one small room with 2, maybe 3 sockets at most, has a separate RFC from the kitchen. In turn other downstairs rooms are on a different RFC. Kitchen also has a 16A radial for a couple of sockets. Yes...odd design.

• Simple and obvious thing is to put back both RFC as currently done.
• Part of me thinks it might be as well making them in to a single RFC by linking ends of each at the CU then remaining ends are a single RFC.

So just wondering what folks on here would think about a pointlessly small RFC in a house with 4 other RFC and a radial.

TL;DR would you merge RFC?

I guess it's going to depend on if merging both rings what appliances are going to be on it, if not a lot of then you may as well merge them.

 

[pc1966]

One of the main reasons for asking here is about the poor sod who follows me. Would such a change be seen as bizarre or not recognised, or if labled would it be understood well enough to allow proper testing or future work?

 

[westward10]

I'm failing to see a problem.

 

[timhoward]

One of the main reasons for asking here is about the poor sod who follows me. Would such a change be seen as bizarre or not recognised, or if labled would it be understood well enough to allow proper testing or future work?

He'd likely be thanking you for one less RFC to test!

 

[brianmoooore]

He'd likely be thanking you for one less RFC to test!

Time saved on that would be negated by wondering WTF are these random 2.5s joined together and tucked away in the back of the CU.

 

[mainline]

Time saved on that would be negated by wondering WTF are these random 2.5s joined together and tucked away in the back of the CU.

Labels work well

 

[7029 dave]

I would keep the circuits as is. Unless you want to omit the cost of an RCBO your call pc

 

[pc1966]

I would keep the circuits as is. Unless you want to omit the cost of an RCBO your call pc

Turns out I have plenty of RCBO and the company who supplied the CU sent a bigger one as the size I asked for was on long lead time. So might as well keep it that way.

Also looking at the old labels it seems the small room RFC also covers part of the kitchen (indeed...)

And as I suspected the 16A radial has most of the heavy kitchen loads