Rewiring Combi Boiler Supply

[davas]

I'm looking to replace the wiring for my combi boiler...

Would you put it on a FCU through the ring main or would you put it on it's own circuit (with appropriate switch)?

Also, what size and type of cable is commonly used?

Thanks in advance

 

[baldelectrician]

its not against the regs to use a spur from the ring main for a combi, but if you are going to do a lot of work in the house anyway I would be inclned to put boiler on it's own circuit as there will still be heating if sockets trip, therefore making life more bearable.

(assuming there is going to be a split board arrangement)

 

[davas]

So on own circuit. No problem with regs as i'm doing entire property through a Building Control Notification.

Should it be protected by RCD or not? And what size would theMCB and cabling commonly be? (It's on my list of things to do to get the correct spec for the boiler)

Thanks again

 

[baldelectrician]

check Ze and cable calcs, but usually 1,0mm or 1.5mm and a 6A mcb will suffice for a boiler

tn supply with good Ze, NON rcd protection may be OK

tt supply or bad Ze RCD protection essential

 

[davas]

I'm getting an TN-C-S arrangement fitted so non rcd protection seems sensible to me. I'll also check the cable calculations when i get the correct spec from boiler manufacturers so that seems to have answered my query.

Many thanks baldelectrician