I'm being P'eeed!

[Ejaz]

yes, as part of my loft extension my builder has arranged for my electrics to be Part P certified by an electrician since the CU was replaced. After his initial visit there was some remedial work required (below) which i have volunteered to undertake. my first question is in regard to earth bonding, i am planning to run the cable from the bonding clamp on the gas meter under the floor and into the kitchen

4) There is no water bonding to the water stop valve in the kitchen below the boiler.
5) There should be 6mm supplementary earth bonding to the boiler pipe-work

So, do i need to bond a all the boiler pipes as well as the water main? also, do i run the cable back to the gas meter or CU?

My second question is about modifying a circuit;
2) The kitchen is wired mainly on two radial circuits, one for the boiler and there are about six sockets connected to the sockets on the left hand side. There is a chance of overloading this radial circuit.

I can connect this to the ground floor ring main but what is the best method, junction box, terminal block? ideally i would extend the ring between existing sockets but this may not be possible

 

[ricicle]

There is no need to earth the water under the boiler if it is (hopefully) done near to the stop-tap.

Supplementary bonding is not required across the boiler pipework.

Are you saying the boiler FCU is supplied via it's own radial circuit (16/20A ?) It may be possible to shift a couple of the kitchen sockets on to this circuit.

Oh, and......
//www.diynot.com/wiki/electrics:part_p

 

[kevindgas]

a kitchen radial is that or make make it a ring by adding a return.
adding it to a ground floor ring in my mind means an even bigger overload and is not good practice.
the boiler will only draw 3 amp unless its something like a Keston (10amp) so won't put any real load on the circuit.

earth bonding - where did you get 6mm to the boiler from? it should be 10mm to the Gas Meter and 10mm to the Cold Water Stop Cock so long as the boiler is connected to the gas and water mains by copper it is already bonded!
if your consumer unit is a 17th edition board then the boiler will be protected. if its an older board then fit a 30Ma switch at the boiler.

 

[ricicle]

if its an older board then fit a 30Ma switch at the boiler.

For what reason ?

 

[Ejaz]

will adding to the ring main really risk an overload? my cooker is gas btw. yes boiler is on its own 6A radial -it's a new vailant on 3A FCU.
CU is a new 10 way with dual RCD (17th edition).
pipe work is copper from boiler but then plastic to/from rads so guessing thats' why all pipework needs to be bonded?.
hey, the leccy says 6mm in his report..is he WRONG?!?!

if overload is a real risk my other option would be to return the radial to the CU and make into a ring then swap the 16AMCB for a bigger one

 

[kevindgas]

if its an older board then fit a 30Ma switch at the boiler.

For what reason ?

stops anyone getting electricuted when a fault develops on the boiler!

 

[kevindgas]

will adding to the ring main really risk an overload? my cooker is gas btw. yes boiler is on its own 6A radial -it's a new vailant on 3A FCU.

it may, it may not it depends on how many electrical appliances you have.

CU is a new 10 way with dual RCD (17th edition).

that's good then you have the best available (until they change the regs again! )

pipe work is copper from boiler but then plastic to/from rads so guessing thats' why all pipework needs to be bonded?.

plastic pipework is non conductive so no need to bond

hey, the leccy says 6mm in his report..is he WRONG?!?!

ask him where he got 6mm from and why, he made the statement.

if overload is a real risk my other option would be to return the radial to the CU and make into a ring then swap the 16AMCB for a bigger one

personally i would make the kitchen a ring in its own right and upgrade the mcb

 

[Ejaz]

ok, since i dont want to start ripping up my lovingly tiled kitchen floor i will just return the radial to the CU and make it a ring.
i just had a thought, i'm sure my plumber used plastic to extend the pipework when he moved the stop cock. If this is the case do i only need to bond the gas meter?

 

[ricicle]

if its an older board then fit a 30Ma switch at the boiler.

For what reason ?

stops anyone getting electricuted when a fault develops on the boiler!

Nothing wrong with adding one, but completely un-necessary as it is fixed equipment and an RCD FCU will not protect the supply cables in the wall !!

The cpc and opd should do their jobs if a fault develops.........

 

[Taylortwocities]

Further discussion re 3omA RCD just for the boiler is pointless because.....

CU is a new 10 way with dual RCD (17th edition).

 

[Ejaz]

hmmmm, also noticed this on the report:
"earth bonding clamp should be no more 600mm away from the gas meter fixed to the solid pipe on the consumer side of the meter."

since I can't move either the gas meter or the CU, what are my options?

 

[ricicle]

hmmmm, also noticed this on the report:
"earth bonding clamp should be no more 600mm away from the gas meter fixed to the solid pipe on the consumer side of the meter."

since I can't move either the gas meter or the CU, what are my options?

How far is the bond from the meter at the moment ?

 

[Ejaz]

well, for a start there is no bonding from the earth terminal in the CU to the gas pipe. the bonding that is on the gas pipe is fixed loosely to the pipe directly where the pipe leaves the meter to supply the house but the bonding cable runs down under the floorboards (presumably this is old cross-bonding?).
i noticed that there is a metal pipe (not gas/water-earthing point?) to which there is another bonding clamp that looks like it#s running up above the CU to where the electric meter and service unit sit..

 

[Electrifying]

Ejaz, who fitted your nice new 17th edition board?

Only asking, because as an absolute minimum the Main Bonding should have been brought up to scratch when this was done, then the installation should have been subjected to the necessary tests, and then, (and only then) should it have been re-energised.

Please don't tell me you fitted the CU yourself.

 

[Taylortwocities]

When the board was changed you should get an Electrical Installation Certificate. This will include details of the presence of bonds to water, gas etc and the size of the conductor.

What does it say?

.