No Bonding to my gas pipe - is it worth adding one ?

Hello Folks.
I have the luxury of being able to access the entire under (ground) floor area of my semi. This is where all of my services enter and exit the house.

I was under the floor today installing a compyter network cable when i decided to have a bit of a mooch around to check all of my visible cables and service pipes for damage and leaks.

I've had a closer look at my earthing and bonding. I noticed that my incoming gas pipe, which was installed about 5+ years ago isn't bonded to anything, it just goes into the house and up into my boiler, I thought it should be bonded within 600mm of entering the house.

Would it be OK for me to add an earth clamp to the gas pipe and connect this to my main bonding point ? The same one that my main water inlet and the Earth from my electrical service head is connected to, or did my Gas central heating fitters leave this off for a valid reason ?

Whilst looking at my G/Y earths and bonding conductors I've noticed that quite a few of the connections are made by baring a section of wire by removing 6 inches of insulation and then 'wire wrapping' the new 'spur' onto this. It all sems a bit gash with too much scope for corrosion and loosening of the connection for my liking, although on close inspection these connections do seem to be quite secure. My house was built in 1987, was this standard practice back then. ?

I have some metal earthing blocks and i was thinging of snipping all of these types of connections and termiating them 'Properly' in earthing blocks.

kwikfix328 said:

...I thought it should be bonded within 600mm of entering the house.

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You thought correctly.

Would it be OK for me to add an earth clamp to the gas pipe and connect this to my main bonding point ?

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Yes, assuming that your main bonding point is connected to an adequate earth.

The same one that my main water inlet and the Earth from my electrical service head is connected to, or did my Gas central heating fitters leave this off for a valid reason ?

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That depends on their reason.

Whilst looking at my G/Y earths and bonding conductors I've noticed that quite a few of the connections are made by baring a section of wire by removing 6 inches of insulation and then 'wire wrapping' the new 'spur' onto this. It all sems a bit gash with too much scope for corrosion and loosening of the connection for my liking, although on close inspection these connections do seem to be quite secure. My house was built in 1987, was this standard practice back then. ?

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It still is. Best practice is to arrange that the conductor is uncut at each termination.

I have some metal earthing blocks and i was thinging of snipping all of these types of connections and termiating them 'Properly' in earthing blocks.

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Don't. That would be improper.

Can you post a piccy of the Main Earthing Terminal (MET) i.e. where all the earths go back to - usually near to the electric meter?
Also those metal blocks, can you post a pic of what you have? The twist around method isn't the best way of making a sound electrical connection.
There should be an unbroken conductor from where your water enters the house to the MET and another from where the gas enters the house to the MET. You can also use the same conductor for both as long as it remains unbroken along its length.

Softus said:

kwikfix328 said:

...I thought it should be bonded within 600mm of entering the house.

Click to expand...

You thought correctly.

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Sorry to disagree Softus, but gas regs state it is withing 600mm of the gas meter or before the first T in the gas pipe work

Spark123 said:

Can you post a piccy of the Main Earthing Terminal (MET) i.e. where all the earths go back to - usually near to the electric meter?
Also those metal blocks, can you post a pic of what you have? The twist around method isn't the best way of making a sound electrical connection.
There should be an unbroken conductor from where your water enters the house to the MET and another from where the gas enters the house to the MET. You can also use the same conductor for both as long as it remains unbroken along its length.

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OK folks here are some pictures, needless to say my missus just loved taking pee as I took photo's of the gas meter

For info: The Gas and Electricity Meter boxes are outside the house, any cables and pipes then pass into the house into an internal cupboard that houses my Main house Electrical Consumer unit and Gas Combi Boiler.

I'm a bit confused with the term MET, i know what it stands for but what is the MET is it the Earthing bar in the CU, The earthing block that these earths are connected into , or the earth connection at the grey service head. ?

The gas meter:


My Electric meter box and service head. ( BTW; Can you confirm that this looks like a TN-C-S type supply ? ) .


I currently have a 4 way version of one of these: , but was going to upgrade to an 8 way one , to connect the earths to.

At the moment The 16mm G/Y from the service head goes into the earthing block, as does the G/Y from the Mains water pipe, from here there is a 16mm G/Y that goes to the CU. From memory there is also a couple of other , thinner G/Y cables that go straight into the earthing bar in the CU, also as i stated earlier there are other earthing wires that are 'wire wrapped' onto the 16mm cable from the Water pipe.

My intention was to fit a bigger 8 way earthing block and also add the new earth from the gas pipe to this.

Obviously as i now have a new Isolating switch fitted , i was going to do all this with power off in the house.

I was planning to end up with something that looked like this picture here , (that i've copied from another website) ,


I have a Megger RCD and Loop tester at my disposal to check anything out that might need checking.
Any helpful and friendly advice is as always greatly appreciated.

gas4you said:

Softus said:

kwikfix328 said:

...I thought it should be bonded within 600mm of entering the house.

Click to expand...

You thought correctly.

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Sorry to disagree Softus, but gas regs state it is withing 600mm of the gas meter or before the first T in the gas pipe work

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Sorry to disagree, gas4you, but BS 7671:2008 (and BS7671:1992) states the following:

The MEB connection to...gas....service shall be made as near as is practicable to the point of entry..into the premises. Where there is an insulating section...or meter, the connection shall be made to the consumer's hard metal pipework and before any branch pipework.. Where practicable the connection shall be made within 600mm of the meter outlet union or at the point of entry into the building if the meter is external.

That may be but the gas regs are what we have to go to and if it is not there or visible it gets a notice to call out a sparks.

More work for you then, easy call out charge

kwikfix328 said:

I'm a bit confused with the term MET, i know what it stands for but what is the MET is it the Earthing bar in the CU, The earthing block that these earths are connected into , or the earth connection at the grey service head. ?

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The MET sounds like it is currently the 4 way block where the earthing conductor from the service head connects, the CPC from the CU and the MEB (main equipotential bonding) from the water all connect.

From memory there is also a couple of other , thinner G/Y cables that go straight into the earthing bar in the CU, also as i stated earlier there are other earthing wires that are 'wire wrapped' onto the 16mm cable from the Water pipe.

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It is these other cables wrapped around the water MEB which don't sound very good.

My intention was to fit a bigger 8 way earthing block and also add the new earth from the gas pipe to this.

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Fair enough, tho can you identify what those other wrapped around earths are connected to? These ideally want sorted properly.

ive had this conflict loads of times now with plumbers.sorry,"heating engineers".i just do what they want as standard .that way we all comply.


they could pay us back by reconnecting MEBs when they work on the pipes,but of course they dont.for some reason they deem it electrical work,which it is ,but come on lads have a heart

Spark123 said:

The MET sounds like it is currently the 4 way block where the earthing conductor from the service head connects, the CPC from the CU and the MEB (main equipotential bonding) from the water all connect.

It is these other cables wrapped around the water MEB which don't sound very good.

Fair enough, tho can you identify what those other wrapped around earths are connected to? These ideally want sorted properly.

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I'll take another look tomorrow, I'm pretty sure though that the thinner earthing cables ( they are either 6 or 10mm ) come from the pipework supplying the kitchen taps and also the the pipework supplying the bathroom ( Bath, Basin,WC ) which is also on the ground floor.
I also have a shower room upstairs ( supplied by my combi - not electric ) and all of the old Water heating stuff, e.g. water tank, immersion hot water tank, etc, although non of this stuff is now working since Gas installation, and i also had a new CU fitted very recently so all of the economy 7 circuits were disconnected and isolated ( but the wiring is still in place ).

I've not seen any Bonding cables coming down from upstairs though...

daytona said:

ive had this conflict loads of times now with plumbers.sorry,"heating engineers".i just do what they want as standard .that way we all comply.


they could pay us back by reconnecting MEBs when they work on the pipes,but of course they dont.for some reason they deem it electrical work,which it is ,but come on lads have a heart

Click to expand...

I always replace any MEB if it has to be temporarily removed for my pipe work, last man on job etc, I'm responsible.

I look at it from job to job, if it is new build or a sparks is on site or has been recently and left a certificate, then I leave alone as he has signed for it. If it is an old property with no certificates I then apply the gas regs, as I am taking responsibility.

I thought this problem had been addressed, but now the 17th seems to have opened it up again

I think it has all been made worse by the limited scope Part P, which I have, but I have now dropped, as it is not worth it IMHO, just another money making scheme for training centres.

Best leave electrics to sparks, but until the regs are aligned we will unfortunately always have this 'debate'

well I dived back under the floors this morning amongst the cement?concrete dust ( horrible place ) and took a closer look at my earthing arrangements and did a bit of minor modification with power off/Isolated.

I fitted a new 16mm² earthing cable from just after where the Gas pipe enters the house to the MET Earthing block- ( nothing blew up when i went power on again)

I also took a closer look at the earthing arrangement that i could see. I've even drawn a pretty picture here :

http://photos.imageevent.com/sidand...forgashpiccys/House Electric installation.JPG


The main 3 Earthing wires go to the MET Block , then to the Earthing Bus in the CU, all via 16mm cable. I believe that they have enough slack in them to connect directly to the CU earthing bus if required ?? this would cut out the earthing Block and also reduce the physical mechanical/electrical connection count.

The wires that are wire wrapped are supplementary bonding cables, coming from various water pipes to taps .

All of the water pipes in my house both tap supply and radiator heating pipes, etc are all copper with soldered connections so they should all be electrically connected anyway, however the pipes coming out of the bottom of the combi are all bonded together , but that is all , there is no flying lead going off to the MET.

I cannot find any Earthing wires that comes from any of the pipework upstairs, although the pipes upstairs do all seem to be cross connected with bonding wires.


Here is a Photo of one of the wire wrapped connections that i found lying in the dust this morning, it initially looked quite strong, but didn't take much manipulation to loosen it off significantly, luckily I am the only idiot in the house that ever ventures under the floors to do stuff. This is typical of the other wire wrapped connections that are still installed.
.

You say you had the consumer unit replaced recently, all this should have been sorted out before that was done.
I don't know why you have 2 cables from the CU to the MET. Is the combi boiler in another building such as an external garage? The kitchen sink does not require bonded. The bathroom should have local supplementary bonding i.e. the pipes together and to all the CPCs of circuits in the zones of the bathroom - it doesn't need to connect to the MET.

Spark123 said:

You say you had the consumer unit replaced recently, all this should have been sorted out before that was done.
I don't know why you have 2 cables from the CU to the MET. Is the combi boiler in another building such as an external garage? The kitchen sink does not require bonded. The bathroom should have local supplementary bonding i.e. the pipes together and to all the CPCs of circuits in the zones of the bathroom - it doesn't need to connect to the MET.

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Yeah, the CU was replaced last week by a local Spark. Basically he ripped out the old two CU's ( 1 x normal 1 x economy 7 , and isolated a whole load of Electrical Heating circuits that are now either not fitted, or obsolete ( Storage heater Radials, Fan/Panel Heates radials, Immersion Heaters, etc ) then Just fitted the new CU with just the circuts that i wanted which were:

Non RCD
Lights Up
Lights down
Garden Shed

RCD
Ring Up
Ring Down
Cooker

It was replaced on an 'almost' like-for-like basis, using the existing Earthing that was already in the old CU's.

I went under the floor to install a new Computer network cable and just decided to get nosey and delve a bit deeper, which is why i noticed these things.

Must dash gotta go to work to do some of my kinda sparkying.. I hate night shifts... .

It's great working shifts
It is a fundamental requirement of the IEE regs that the earthing and bonding should have been checked before any alterations or additions are carried out.
I take it he gave you the electrical installation certificate?