A smart meter couldn't be installed because of an earth cable - why?

Hi, The OVO engineer has refused to install the gas smart meter (there is currently a BG one in situe but the OVO meter is considerably larger. Apparently the "Earth Ground Cable" is preventing the meter being "raised" to install the OVO smart meter in place of the BG one.

Whilst its frustrating that there was no standardisation of the sizes *at the very least*, I have just spoken to an electrician who I used to meet at my networking group and he thought the installer must have been a "wet behind the ears type who didn't want to bother". I have to say I was very surprised that a qualified engineer wouldn't do something as basic as this as part of the installation as it looks like its a simple matter of unscrewing the cable connection and moving it to the back of the pipe.

I've attached pictures - could you tell me what needs doing so that the "fully qualified" engineer can come back and finish the job.


Best answer by Eva_OVO 14 June 2018, 12:24

Thanks for posting, @Geo

Although the engineers are fully qualified, they’re not insured to move the earth cable. The earth cable is essentially part of your personal electrics, so you’d need to contact an electrician to move it. I’ve spoken with the experts about this and if the electrician can move the cable the maximum amount away, our engineers will be able to exchange the meter.


Updated on 12/07/2019
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It is because smart meters use mobile technology to send us automatic meter readings that reflect the exact energy we use.
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Thanks for pics @Solarpayz These help a lot.

So your gas meter is in an external semi-concealed box (like mine). I'm a little surprised to see that the exit pipe leaves the box in copper pipe rather than having a joint at the point where it passes through the plastic side wall.

Have a look at the photo of my gas meter here on this Topic, as it was a year ago.

You can clearly see that there is a joint at the exit point from the box. Anything inboard of that forms part of the meter connection pipework... and thus isn't a point where the earth wire should be attached.

The photo I've just mentioned clearly shows my earth-bonding point, about 100mm from where the pipe actually enters the building.

Now have a look at this photo of a SMETS2 meter installed in another semi-concealed box (not mine). It clearly shows the new arrangement of meter connection pipework, which I've marked with red arrows. The exit pipe to the right is a welded steel angle which terminates in the joint where the pipework leaves the box.

I think the correct place for your earth bonding is right next to the brick wall where the copper pipe finally enters the house. This means it will be attached using a banded connector which is weatherproof. I can't tell if your existing one is, but the blue colour of the tag suggests so.

I don't know if you are on a PME electric supply or whether you have your own earth stake. However, the house is 12 years old and soil conditions will have settled somewhat during that period. It wouldn't be a bad idea to request than a local electrician not only moves the gas bonding point, but also checks the earth resistance for your house.

This is, after all, a safety feature!
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Here is my gas meter box with its earth wire:

I would like like to know if it looks as if this complies and what needs to be done with the earth wire to accommodate the gas smart meter.

many thanks
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Thanks @Transparent for the reg reference.

OVO told me the earth wire is on the wrong side of the meter box and should be moved back as far as poss as in:

”The electrician will have very strict rules about where he can move the earthing wire. However if you could ask him to move it as far back as possible that would be ideal. “

I'll post a photo tomorrow when we have daylight.

thanks again.
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Thanks @Solarpayz - you're right; the purchase date is far too early for the issues which have just surfaced. Even an NHBC warranty would now have expired.

There is no OVO Spec for meter positioning.

The relevant points are that the earth bonding should comply with the Wiring Regulations. In 2007 this would've been the 16th Edition. Thus the earth wire needs connecting to the bare metal of the gas pipe as close as can be achieved to the point of entry into the building, and certainly no more than 600mm from that point.

It's the home-owners responsibility to ensure that the electrical installation within their house remains safe and functional. So it's not just a matter of where the earth-bond connects to the gas incomer, but where the other end of that wire goes to!

I've had a second earth-stake installed about 8 years ago (I'm not on PME). The original one no longer provided an "adequate" earth because the ground had become drier and the resistance reading was too high. I also have two further earth points as part of the anti-surge protection for my off-grid renewable energy system.

I appreciate what's involved in an earth-bonding scheme, and I have mine re-checked whenever a certified electrician comes here, even if it's to do other unrelated work. The test takes less one minute.

It's a bit difficult to state anything more about your situation without seeing a photo of your present gas meter set-up. Are you able to post one here?
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I bought into this estate early (2007) from John Laing Homes just before they were bought out by Taylor Wimpey.

I’m not sure if this is recent enough for your letter.

I've not checked closely the gas meters on the most recently built homes.

Please see the link for the other builders involved.

Gloucester City Council is the LPA for Kingsway Village.

My main concern now is to have OVO’s spec so my electrician is assured of meeting their requirements.
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Please tell me more, @Solarpayz

I am about to write to my MP regarding a problem which has occurred due to the effect of the 2015 Deregulation Act on the way in which energy matters are specified for new-build homes. I need to know quickly if this is behind the issues you are now telling us about.

Firstly, I need to identify your LPA (Local Planning Authority). Your Forum Profile says you are in Kingsway. Which one? London or Cardiff?

Secondly, which of the national house-building companies have been involved in this estate of 2500-ish houses?

Thirdly, only the "Big-6" Energy Suppliers have the authorisation to install meters on large new developments. Do you happen to know which company was responsible for installation of the initial gas meters? (This will be the company that is the Supplier by default when a house is first occupied).

Fourth; For your particular house, are you the first owner?
If so, were you given
  • a 2-year guarantee by the house builder
  • a 10-year warranty, usually from NHBC
  • a Building Regulations Certificate
  • or something else?
The earth bonding for your gas meter is defined by the Wiring Regulations current at that time. It must comply with BS7671.

The Building Regulations (Part-P) state that such an installation may only be carried out by a qualified and competent professional. Thus it is the certified electrician who connects the earth bonding to the gas pipe, which must be within 600mm of the point of entry to the building.

None of this changes when a meter is changed, either replacing a faulty one or installing a new Smart Meter. There is no need for the companies involved in fitting Smart Meters to agree any new specification.

So, just what have they "got wrong" on your new estate?
Have they connected the bonding to the meter connection bends rather than to the entry point of the pipe into the building?

How sure are you that this is reflected across all other houses on the estate?

Could it not merely be the work of one less competent electrician?
Perhaps the one person worked on only a proportion of the homes.
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If my gas meter earthing is wrong for a smart meter then so are the 2,500 recently built homes on my estate.

Not only did the geniuses behind the smart meter initiative not agree a standard before they started work, they also failed to inform builders of their requirements.

It’s a mess.
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Thanks for raising this again @Solarpayz

As I now understand it, the issue isn't primarily about the state of the earth bonding connection adjacent to the gas meter. Rather, it is the unknown state of the rest of the earth bonding within the rest of the house.

The Meter Installer isn't qualified or authorised to check that the earth bonding system is adequately connected to the appropriate earth point. In fact, the Installer doesn't even carry the equipment required to perform such checks.

The earth bonding used in UK houses isn't uniform. Some houses must have their own earth stake, whilst those fed from a sub-station designed for PME should not have their own stake unless the DNO identifies that one is required.

Failure to implement the correct system can have serious consequences. If a stake is added to a PME installation, then a fault in the neutral feed can leave houses beyond that point with their own "earth" floating at 80v or above. This would cause electric shocks, and possibly fire.

I have visited a site where an Energy Supplier had subcontracted a Smart Meter installation to a company which had not instructed its engineers on this issue. He had installed a fresh earth wire to a new copper-clad stake outside the front door, which also lacked the required test-point at the top. In fact the reason there appeared to be insufficient earthing to the property was because of corrosion on the decades-old feed entering the property.

Local electricians working in an area know about these matters and have the right test-gear. They are also aware of when they need to notify the DNO for that region and request that they attend on-site to make good damaged feeds.

Where I do agree with you is that there should be an OVO-issued Notice at the time when a customer books a Smart Meter installation. This would provide adequate warning of the possible problem, and allow the householder time to get an electrician to do an earth-test. If, at that time, the inspection finds that the equipotential bond is not within the correct distance of the gas meter, then it can be moved.
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This seems to be a handy excuse for OVO not meeting the government target for installing smart meters.

"Sorry, Guv the homes were not built properly".

Also, knowing these additional costs it is wrong for the smart meters to be advertised as "free".

A choice was made to not train or insure the smart meter installers to do all the electrical and gas work necessary to install the smart meters.

Have all the energy companies made this decision in this way or just OVO?

At the very least OVO should be issuing a spec or dwg for its customers to issue to their electrician so we are sure of fulfilling OVO self-imposed requirements.
@Transparent The existing smart meter is a British Gas one.

The space around my meter is actually quite substantial despite the carpet needing a trim in the photos, which I've now done. The OVO meter is so large though that even in what I would call a moderate environment it can't be fitted apparently.

I understand the idea of regulations and the principal behind the earth bond but I fail to see why the engineers can't just move it, its just a simple wire with a fastening buckle, its not hugely substantial a task - they are qualified to install what is an electrical item to the gas mains so moving them them should form part of basic training and ergo the insurance if that's the real problem.

I'd have more sympathy if my issue involved re-piping the gas meter and soldering new parts to it - that's above and beyond a smart meter install but a five minute job moving a wire is frankly what I'd expect any self respecting engineer to be able to do. (and actually what my networking professional contacts say should have been done - they are all time served gas/electric engineers and work on large and small domestic and commercial properties I'm not kidding when I say they were extremely bemused by this thread.)
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Firstly @Geo I'd like to thank you for raising this Topic on the Forum in the first place.

I am continuing to have discussions with gas-fitters and electricians about the secondary issue of Equipotential Bonding. In my area of rural Devon, it seems that very few houses have installations that have been checked and certified for compliance.

I have yet to find anyone local to me who has had a Smart Meter installed, where the earth bonding was even raised as a issue. It wouldn't surprise me if more than half of these installations have been completed despite the earth-bonding regulations having not been complied with.

And yet, you would have expected the opposite... that the Smart Meter installation would be an opportunity to bring domestic properties up to the basic safety standards!

Returning to your primary point about the physical size of a meter:

I have never seen a gas meter as small as the one you showed in the photo at the start of this Topic.

There may well actually be a standard for a maximum size. I need to check this.

But if a previous installer has fitted a smaller than average meter, then of course this can create a problem when that meter needs to be changed at a later date.

What's required is a standard "envelope" of 3D space which should be left around a meter such that any exchange can be done effectively. This envelope would also incorporate the designated positions for the support bracket and connections of course.

Such a standard does already exist for the manufacture of external wall mounted meter-boxes (both flush- and surface-mounted designs).

This isn't just an OVO problem. It's industry-wide.
I have to confess I've given up - I've spoken to electrician and gas business owners through my networking contacts - these are professional friends who all think this is a complete comedy that your employees or outsourced contractors are completely hamstrung by your own internal politics.

Whilst they are friends I won't ask them to work for free to fix an issue which your installers should be undertaking anyway. Frankly if you (OVO) have a smart meter which is bigger than any other suppliers meter (and it should be a standardised size anyway!!) then its your problem not mine. I'm over half way through my contract and frankly I'm not paying any more money for stuff to be done to fix a non-existent issue in my eyes. I'll simply just move to a different supplier to get a smart gas meter again.

From all this discussion there are three key learning points for you:

You need to (a) train your engineers to do the basics (b) insure them to do so and (c) change the meter so that its smaller so you match other suppliers sizes which will save you 80% of the aggro of having a larger meter when it comes to install time.
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Thanks very much for pursuing this @Nancy_OVO. I appreciate what you've written and the time put into this by other OVO staff.

For the sake of clarity for others trying to follow this:-

I think it's important to realise that simply replacing the earth bonding onto a gas pipe doesn't mean that it's effective. The Installer would also need to test that the other end of the earth wire is correctly connected to the same earthing point used by the Consumer Unit, and that this had a properly installed route to earth, either via an earth stake or through the neutral of the incomer (PME supplies).

If an Installer simply replaced an earth bond which was there when he arrived, it would give the home-owner an assurance that all was safe, when in fact it might not be so.

So I understand why OVO's Engineers and legal bods are taking the stance they are.

Nevertheless, I still think that there should be Written Notification of the need to have earth-bonding tested on three occasions:
  • Online when a customer books a Smart Meter installation
  • By email or post once the booking is confirmed
  • By hand from the Installer when he attends on-site

That would bring a fair balance to the interests of OVO in not being held liable for the status of the Earth Bond, and the responsibility of the Owner/Occupier to maintain a safe installation within their home.

I really don't think customers are going to be looking up Sections 6.2 & 6.3 of OVO's T&C's when requesting a Smart Meter installation!
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Hello again @Transparent, @PeterR1947, @mikeb and @Geo!

I've contacted our Compliance & Regulations team and our Engineering Operations Managers to get some more information on this and I've been advised the following:

Engineers are not permitted to re-position, alter or extend bonding without the required qualification - Equipotential Bonding (PEB1). The reason being, they're unable to test the bonding is in working order once the circuit has been broken.

I've also been advised that we have been looking into the possbility of providing this training, but we need to weigh up the benefit (being able to complete more jobs) against the cost of retraining all our engineers. Our figures show that we don't abort many jobs due to Earth Bonding posing a problem, so it may not be the right thing to do commercially.

Compliance & Regulations pointed out a section of our Terms and Conditions regarding meter maintenance:

"6.2 You are responsible for ensuring your property has an appropriate credit meter or prepayment meter installed that meets all the following requirements:
(a) it is capable of measuring the energy supplied to your property;
(b) maintenance and legal compliance checks are carried out for all pipes, equipment, wires and other fittings; and
(c) it is suitable and meets industry standards for safety and accuracy

6.3 You are responsible for ensuring that your metering equipment is not lost, stolen or damaged. In this contract metering equipment means the meter itself and all equipment required to operate your credit meter or prepayment meter."

Hope this helps clear things up,
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Thanks @Nancy_OVO,

Coincidentally, I had a visitor here yesterday who writes British Engineering Standards Documents! I was able to show him this Thread and his opinion was that there was an unspecified area between the tasks expected of a Meter Installer and an electrician.

However, as it's a matter of public safety, it is vital that this is resolved urgently. There are probably already several hundreds of Smart Meter Installations where the earth-bonding to the gas pipe has been compromised but the householder is unaware of this.

My view is that Ofgem should be alerted and ask for guidance. After all, they're the industry Regulator. It's their role to regulate!
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Hi @Transparent and @mikeb,

I'm not an expert in industry regulations, so I've asked our Legal team for more information about this and I'll update everyone once they've responded.

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Well done for persistence @mikeb :)

I realise that the helpful member of OVO staff in Customer Services is going to "feed this back", but it would probably be more helpful if the relevant Dept could have their attention drawn to this Forum Topic.

After all... this is a safety issue!

... and you've helpfully quoted from the relevant regulations.

The Moderators would know who to notify about the issues raised here. @Nancy_OVO are you able to send an internal message to a relevant person, please?
Good morning Transparent,

I have just come off the phone after a long discussion with a lady at Ovo. In simple terms the issue with my installation is that in order to fit the smart meter the engineer may have to alter the outlet pipework which will require the removal of the bonding clamp. As the engineer is not a bonding clamp competent person he is not allowed to do this and the installation would be aborted. If however the clamp is not in its present position there will not be an issue and he can do the job. Simple!
I suggested that this must be a common enough situation to warrant inclusion in their 'get a smart meter' blurb to avoid the inconvenience and aggravation of aborted installations. It also calls into doubt the claim that smart meters are free if the customer has to pay (possibly £30-£40) for reconnection and testing of the equipotential bond. She accepted these points and said she would feed it back.

Interestingly there was no mention in the engineers report of the need for a longer inlet pipe - the only reason he gave me for not being able to complete the installation. I now have a date at the end of July for the job to be completed.
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That's excellent research @mikeb. 🆒

... and by the way, my Forum User-name is @Transparent, whereas Ninja*** is the badge given to me by the Moderator team!

1. I think your analysis of the Regulations is correct. There should be a Notification about Earth Bonding given in writing when Smart Meters are installed. There are three places where I think the Notice should be provided:
  • on the OVO website page when booking a Smart Meter installation
  • on the email/letter confirming the booking (so as to ensure those who didn't book online still receive the Notice)
  • on a card to be given to the householder at the start of the installation works

Frankly it shouldn't matter whether an earth bond gets disturbed or not during a gas meter installation. If the card is properly worded, it should serve as a timely reminder that we are all responsible for checking that we have homes with safe electrical connections!

2. I've also just checked Part-P (Approved Document) of the Building Regulations. It starts like this:

1.1 Electrical installations should be designed and installed in accordance with BS 7671:2008 incorporating Amendment No 1:2011.

Provision of information
1.2 Sufficient information should be provided to ensure that people can operate, maintain or alter an electrical installation with reasonable safety.

The information should comprise items listed in BS 7671 and other appropriate information including:

a. electrical installation certificates or reports describing the installation and giving details of the work carried out

b. permanent labels, for example on earth connections and bonds, and on items of electrical equipment such as consumer units and residual current devices (RCDs)

The provision of Information therefore lies at the very foundation of Part-P.

The next page states:

1.6 Regulation 4(3) states that when building work is complete, the building should be no more unsatisfactory in terms of complying with the applicable parts of Schedule 1 to the Building Regulations than before the building work was started...

I would claim that the installation of a Smart Meter without providing the Earth-bonding Safety Information has left the "building work" in a less satisfactory state.

Of course the Meter Installer could claim that they don't work to BS 7671 in the first place...
... to which I think we could now all say "believing that we can work on a building without reference to the regulations is what happened at Grenfell Tower!"

3. I take your point that the equipotential bond should be within 600mm of the output side of the gas meter. However I've seen domestic dwellings where there's 10m of copper pipe running next to electrical cables before it even reaches the gas meter!

So common sense suggest to me that a competent electrician would probably place a bond both at the point of entry to the building, and on the output of the gas meter.

There's no harm in having extra earthing connections. Looping the (uncut) bonding cable across multiple copper pipes is very much at the heart of equipotential bonding!

This is a section of the earthing for my own water pipes leading to/fro my thermal store. Note also the clear printed label on a valve and red colour-coding on two of the pipes!
Ninja***. Many thanks for your comments. I've done a little more digging and found the following at

Wiring Regulations - BS 7671
This technical guidance concerning the application of the requirements of BS 7671: 2008 (as amended) Requirements for electrical installations has been discussed and agreed by a forum, the Wiring Regulations Advisory Group,

Q1.46 In a building where semi-rigid gas pipe is installed, where is the appropriate position to connect the main protective bond if the gas meter is: (a) internal to the building (b) external to the building?
No attempt should be made to make a bonding connection directly to semi-rigid pipework.
(a) Where the gas meter is installed inside the premises, the semi-rigid pipework will normally end at the meter and so the bonding connection should be made as normal to the consumer’s hard metal pipework after the meter and before any branch pipework. Where practicable the bonding connection should be within 600 mm of the meter outlet union.
(b) Where the meter is external to the premises in a wall-mounted or semi-concealed meter box, the bonding connection should be made to the consumer’s hard metal pipework and before any branch pipework. Where practicable this connection should be made at the point of entry to the building.
Regulation number(s)

This guidance indicates that the bonding connection must be on the consumer side of the meter before any branch and if practicable within 600 mm of the meter exit union.

If we also look at (Safety in the installation and use of gas systems and appliances) Regulation 18-2 states
(2) Any person who connects any installation pipework to a primary meter shall, in any case where equipotential bonding may be necessary, inform the responsible person that such bonding should be carried out by a competent person.

The guidance included with Regulation 18-2 states
202 The person who installs a section of pipework which connects with the primary meter or emergency control, whether or not the meter or control has yet been fitted, must inform the responsible person for the premises (builder, owner or occupier) of the possible need for MEB where such a requirement did not exist before the work was undertaken. Such bonding should be carried out by a competent person (see regulation 3, Qualification and supervision, for details on training and competence). The advice should be in writing. Although the regulation applies only when new systems are installed and existing ones are modified, similar action needs to be taken if an engineer notices an apparent defect in bonding in other circumstances, eg during maintenance checks (this applies to both main or supplementary equipotential bonding

The emphasis in this para is mine.

I would suggest therefore that the simple solution is that if the Ovo engineer has to remove the bonding to carry out his installation of the smart meter he issues a notice in writing to the consumer telling him that it must be reconnected by a competent person. I do feel however that Ovo should make clear the possibility of this situation arising in their information about the smart meter installation process. That way people can make their own decision to proceed and fruitless visits possibly avoided.
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As a follow-up to what I've just posted, could you also have a look at a Topic I've placed here about the shortage of Smart Meter installers?

I note @mikeb, that you too are in Devon, where there are long delays in obtaining a Smart Meter appointment.
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Oh @mikeb, what a palava! You appear to have waited six-months due to incorrect advice.

1. Once more I am astonished that a meter installation cannot proceed at all due to the presence of an earth bonding connection. It is blindingly obvious that a high proportion of gas meters will have this earth point very close by.

If the Meter Installers aren't even prepared to touch it, then there will be a corresponding need to revisit the same premises to complete the meter upgrade. This is a sheer waste of time & money.

Common sense suggests to me that OVO should notify all Customers in advance of the agreed Smart Meter Installation date that they should book an electrician to attend about an hour after the works commences so that a fresh earth-bond can be made and tested.

Even if the Installer finds that there is a bond in place and an electrician hasn't been called, then he could mention this at the start of his visit. You'd still have a couple of hours to call an electrician whilst the meter replacements were being fitted.

2. An earth bond to the gas pipe is a statutory requirement.

There are a number of reasons it is there, and they all relate to safety.

If an electrical fault occurs in the house which makes the gas pipe go "live" (a rodent chewing through an adjacent cable) then it is important that the fuse/trip for that circuit must operate. The 10mm earth-connection ensures that sufficient current will flow to do this.

You should certainly not have been informed that your earth-bond was no longer required! This is a safety error, and should be reported in writing (email) to OVO. Since the Installer may have been a sub-contract company, it is OVO's responsibility to sort this out.

3. The presence of the 15mm T-off close to the output of your gas meter isn't a problem at all.

The guidance is that the earth-bond should be made within 600mm of where your gas pipe enters the property. In some cases this means it will have to be on the other (input) side of the gas meter.

Please post here again if you want any further clarifications.
I have a very similar problem.
Just before Christmas the OVO engineer came to fit Smart meters for electric and gas. Electric was fine but he had a problem with the gas. As can be seen in the photo our existing meter is out of the arc, enormous and floor standing.

The new meter is apparently much smaller and he explained that the flexible feed pipe from the cut off valve to the regulator would be too short. He volunteered that this was a known problem but they were not allowed to carry the available longer pipe, it would have to be specially ordered. He said that someone would be in touch as soon as it was available.

Having heard nothing for 6 months I raised a query with customer support asking when they were going to complete my switch to smart meters. On Sat last I had a call from Ovo saying that it was nothing to do with the length of the pipe, they could not complete because I have an earth bond clamp on the pipe. They will not come back until it has been removed. I asked if that was because it was no longer required and he said "yes"!!

My interpretation of the regulations is that the bond to earth in the consumer unit is required and the clamp has to fitted on the outlet pipe from the meter prior to any branch pipes. You can just see in the photo that the clamp is fitted very close to the meter as there is a 15mm branch (to the gas hob) about 2 inches from the meter connection. This obviously precludes moving the clamp further along the pipe.

If Ovo are adamant that their engineers, although able to safely refit the mains cables in the electric meter, cannot be trained to refit and check the bonding clamp, this should be made very clear in the FAQ section of the info on Smart meters.

I would be interested to hear the Ovo moderators comments from the 'experts'
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Hi @Geo,

I think it has been useful to air these issues here, although the answer isn't probably what you (or I) had hoped for.

Would you please let us know when you actually get the gas-meter replaced and tell us how it went?

The remaining matter which still troubles me is what happens to other customers receiving a Smart Gas Meter install, whose earth-bonding clamps get compromised in the process, but who are then not informed that they need to subsequently call in an electrician?

Although we now know that an Installer won't touch or check the Earth-Clamp, there is still the likelihood of its resistance increasing due to heating/cooling during soldering, acid-flux dripping into the clamp-band or application of "gunk" to screwed fittings etc. Such issues will reduce the effectiveness of the earth bonding, which is there to ensure the safety of occupants.

I would've thought it very likely that an earth-clamp will be located in close proximity to a gas meter. The chances of an Installer meeting such a scenario would seem to be sufficiently high that all Customers should be issued with an official Safety Notification to have an electrician check their earth-bonding following a gas-meter replacement.