Safety Check Weirdness

4 Jul 2018
Reaction score
United Kingdom
First post, and treading warily...

Selling my place and have been asked for a Gas Safety certificate. Not a problem.

House built 2010. So installation was signed off at that point.
Then rented out, so landlord certificates would have been done.
I purchased 2013. Another check done. Passed.
2016 another check done. Passed.

A Gas Safe guy comes yesterday...

Tells me that the flue is horizontal not angled, but from what I have read the angle is internal, not external, hence the flue through the wall may be horizontal but the internal slope gives it the 3%. Can anyone confirm this?

Tells me that the isolation valve for the gas hob is a sort that has the potential to leak. It doesn't leak, the hob works perfectly. He has threatened to condemn the system if I don't agree to have it replaced.

Two grommets missing on boiler, fair enough, its a sealed condensing boiler.

Earth. This runs to ground outside of the kitchen. He tells me that although this is only NCS for a gas check, he is a qualified electrician. He then tells me that the hob should have a 3 amp fuse on it, and to install the fuse, he will have to re-route the gas earth.

I have no idea why this system which is only 8 years old, and that has passed numerous inspections, and that has never been touched, should now be at 'warning' level and under threat of being condemned if I don't agree to the work being done.

I am awaiting a response from Gas Safe, who take 5 days, but in the meantime I was wondering if any qualified gas engineers on here can tell me how I get out of this quagmire. I have paid him £90 for the check, and it sounds like there is a hefty estimate on the way to fix all of the problems that he has discovered?

Hoping someone can help.
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What boiler is it? Some flues do have internal fall, so may be ok providing no additional extension pieces on it as they don’t have a fall iirc.

In my opinion, as long as it’s a gas fitting/isolation valve then as long as not leaking then can’t see why it would be a issue.

Not sure Reg the Hob electrics if I’m honest. Central heating systems run of 3amp usually but unsure on hobs
Thanks for the response.

Its a Vaillant Ecotec Pro24, top flue exit, (I understand the pipe is angled to something around 89%) then straight through a wall and vents outside, no extension pieces it's about as short a run as could be. He was placing a level on the internal bracket and saying it was horizontal, so needed fixing? Claimed that the slight discolourisation on the rendered wall outside was a health hazard etc. It is hardly visible, and probably just 8 years worth of accumulation.

I am thinking of getting a second opinion, as the verdict on the hob isolation valve is odd. Any valve has the 'potential' to leak, even one that he replaces it with. It's not leaking at all, and all four rings on the hob work perfectly. Quite where he got his information on these 'known to be defective but they still sell them' valves, he didn't say.
Regarding the missing grommets, have these been replaced or has the boiler been capped off?
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Can't you fine from the 2016 paperwork who did it then and get him back - if nothing's changed.......
That was my original plan, snag is due to the aborted house sale 2 years ago, the certificate is with solicitors hundreds of miles away, and they haven't sent me a copy so that I can get the details. I got fed up waiting so chose another local firm at random. I happen to have a friend who is an ex BG gas engineer, who knows my place, and his view is that if an isolation valve is not leaking, and the hob is working normally it cannot be condemned, the same valve is on sale at Screwfix, labelled as BG approved, so as to how it can be a 'potential' leak makes no sense at all.

Regarding the missing grommets, have these been replaced or has the boiler been capped off?

These I am happy to have, I can see the logic on a sealed condensing boiler, though by pure chance I have had a carbon monoxide sensor right underneath where they should be and it has never gone off. There are two missing on the left. One is where the installers ran the cabling in for the wireless thermostat, and another is a spare empty hole.

I may well have to shell out another £90 for a second opinion if I can get the details of the guy that tested it last time.
Tells me that the isolation valve for the gas hob is a sort that has the potential to leak. It doesn't leak,
Your inspecting technician has seen the valve,so he has an advantage over us ;) he has noticed something :idea:.
Not all valves are the same.
Post a photo of the valve,showing the rear part :idea:
Personally I think he is completely OTT in every fault he has found.But in the litigeous H and S obsessed environment we find ourselves in,and rules and regs sometimes a grey area this crap happens.3degree slopes,3amp fuses.....god help us
I think he is desperate for work if he fartin about with all that caper and nonsense...or rippin the p out of his customers
Your inspecting technician has seen the valve,so he has an advantage over us ;) he has noticed something :idea:.
Not all valves are the same.
Post a photo of the valve,showing the rear part :idea:

I can't, it is an integral oven and the valve is behind it. He pulled the cooker out to look at the valve. It's just a plain brass isolation valve, the tap type, still like new, as is the pipework and joints. He didn't notice anything other than the valve, he just took one glance at it and declared it a known source of potential leaks? If he had provided some evidence to back up his claim I would be prepared to believe him, but he just made the comment and then went looking for other things.

If anyone in the industry is reading this and is aware that there is a gas isolation valve that is a potential leak hazard, but that is still on sale, and must be fitted in thousands of homes, I would love to hear from you. It must surely be common knowledge amongst engineers. Is there even one on the market?
There was an issue with some of them isolation valves in the past,doubt the new valves have the same issue.
If the installation passed a drop test I do not know why he hooked out the cooker to check pipework behind.
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Apart from all metal gas cocks ,gas valves should be manufactured to bs. En 133. If a gas man suspected it was not suitable , his job is to correct it.
Its a brass valve, and can only have been fitted in 2009/10 when the property was built.

I took a look at the Vaillant flue installation instructions.
The air/flue pipes of the horizontal wall penetration are not concentric. With the wall penetration fitted horizontally, the flue pipe slopes downwards at 1.5° towards the inside.

Putting a spirit level on the internal flue pipe clamp shows bang on horizontal, however the internal flue outlet angles up at 1.5 degrees inside the flue pipe. There is apparently a flexible coupling inside, so the 3 degree rule may well be met. If the clamp is not perfectly square on the 87 degree elbow there will be an inaccurate reading.

The guy has sent me a quote that will total £550.

The installation has previously passed the initial installation test and two subsequent ones. They missed the two missing grommets, but they are only £10 a packet.

I am tempted to get another test done, hopefully by a previous test engineer, I've even sent the same pics to Gas Safe for their opinion.


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