Just had my boiler services and test was 28.23kw/hr on a 30kw/hr boiler. This result was after running at this max for 2 minutes. Therefore I have calculated the following 28.23/60*2=0.941Kw use over the 2 minute test. Gas meter reading used 0.096m³. Using the standard m³ to Kw calculation 0.096*40*1.02264/3.6= 1.09Kw. This means that the gas meter is reading 16% more than the actual gas used on the boiler test. Can anyone confirm that I have calculated this correctly and if so I thought the accuracy of a smart meter had to be a lot more accurate than this.
Gas meter accuracy
- Thread starter Mr Parry
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Welcome to the Overclockers UK forums, filled with the leading boiler experts in the country 
That 30kW rating is for the output, not the amount of gas burned. How old is the boiler and what is its efficiency rating? Don't know the details, but efficiency over time can fall and some boilers are never as efficient as they are supposed to be when installed in a real house rather than a lab.
That 30kW rating is for the output, not the amount of gas burned. How old is the boiler and what is its efficiency rating? Don't know the details, but efficiency over time can fall and some boilers are never as efficient as they are supposed to be when installed in a real house rather than a lab.
Soldato
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Am I understanding correctly here - you are assuming 100% conversion of the gas burned into energy ? No boiler is 100% efficient - so back of fag packet would be yours is ~85%.
Surely asking the engineer who serviced the boiler would be a better start than a computer forum though.
Surely asking the engineer who serviced the boiler would be a better start than a computer forum though.
Im asssuming my boiler is runnig at 94% efficiency if the net reading is 28.23kw on a 30kw boiler
Have you factored in the gas in the pipework from the meter to the boiler?
Our boiler has a 22mm pipe feed & is approx 10m from the meter so there's about 0.22m sq of gas that's passed the meter but not yet used by the boiler.
Our boiler has a 22mm pipe feed & is approx 10m from the meter so there's about 0.22m sq of gas that's passed the meter but not yet used by the boiler.
My boiler has about 1.5m of 22mm pipe to the meter. Im just trying to work out if my meter is faulty but factoring in all the things that you are mentioninig it may be ok. Im not educated in the boiler and plumbing world to pocess the knwoledge that you have so Im probably guesiing that things are not as bad as I first thought. Is that your opinion too? PS thanks for your time regarding this.
This forum does genuinely seem to have people from all walks of life with all types of experience.Welcome to the Overclockers UK forums, filled with the leading boiler experts in the country
so the engineer monitored the gas flowing into the boiler over 2 minutes and that corresponded to 28.23kw/hr ? and, has potentially duplicated your calculation to calculate that power,
but that does not match the meters calculation. ?
(so efficiency of the boiler is irrelevant)
Surely that is only a problem on day 0 and never again?
Stay patient. I am waiting for OP to state he has chosen a professional to diagnose his high bills and has now saved $$$$ working from the comfort of his own home.
....
seems gas can vary between 37.5 & 43 Mj / m3 (http://mip-prd-web.azurewebsites.net/DataItemExplorer/Index )
so the enginer used different calorific value to you ...
Soldato
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Too many details missing for a conclusive view. For instance was your boiler firing temperature at maximum or minimum, what was the return temperature of the water like hot or cold. Performance testing is all about the details it's unlikely your boiler engineers test is going to tell you much more than is it hitting it's output target.
no. - can't easily capture calorific heat output of boiler.
can even see hows the calorific (e: gas) value evolves where you live
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www.gasnetworks.ie
so engineer just made calculation, from volume, with a different value, to OP
www.justintools.com
can even see hows the calorific (e: gas) value evolves where you live
Daily Average Calorific Values (CV) at 15 CV Zones
www.gasnetworks.ie
so engineer just made calculation, from volume, with a different value, to OP
Convert Megajoules to Watt Hour (MJ to Wh) | JustinTOOLs.com
Convert Megajoules to Watt Hour (MJ in Wh). Megajoules and Watt Hour both are the units of ENERGY. See the charts and tables conversion here!
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You can be one of the people who calls energy providers to complain that the gas meter is recording more than it should because they are evil and trying to rip you off.
Your provider (as they technically own that meter) wil ask you to prove it through mutliple meter readings, and compare it to the previous year.
Or if the smart meter side of things is working they will be able to see the usage themselves and do an internal investgiation on the account.
When inevitably they find nothing wrong, you can complain and then be put onto a BIG list to have an appointment at...some point.
Normally its eaiser to have a smart meter installation booked if you don't have one already as its the quickest and fastest way to have the meter looked at/replaced with a new unit. In your case this is probably not an option as you have one already.
In 99% of situatioins there is never a problem, over 5+ years on the phones, I came across ONE actual problem with a very old gas meter, with hundreds of "complaints" from angry people who didn't accept there was nothing wrong from a trained engineer because they know better than people actually trained in the subject. You are reading FAR to much into it, trying to prove there is an issue.
The simple answer will be the calorific value that was used to make the calculatioon along with many other factors not easilly reproduced
From someone who had to take calls from people like yourself, please dont call, they have it bad enough with the complaints about the cost of living crisis and people complaining about the high costs thinking the agent on the other end is personally responsible that they are in debt. They don't need pointless calls on top of that.
Sorry about the aggressivness by the way, I had to speak to so many people over the years who just whined and whined about the meter recording more than they where using (which is virtually impossible nowdays) while smiling and nodding along in the hopes they didn't want to raise a complaint as then I would be stuck with them for weeks on end until an appointment was completed, then having to tell them there is nothing wrong.
The go to response would be if you think your meter is faulty, get a smart meter installed, which people didn't like to hear, they are paranoid already so think smart meters are evil and are information gathering devices to do....something outside of recording energy used.
You would then have the awkward manager call requests from people who just didn't accept the conclusion even though they have ZERO evidence of anything and having to justify the callback to your manager which was difficult most the time to get them to do it.
Your provider (as they technically own that meter) wil ask you to prove it through mutliple meter readings, and compare it to the previous year.
Or if the smart meter side of things is working they will be able to see the usage themselves and do an internal investgiation on the account.
When inevitably they find nothing wrong, you can complain and then be put onto a BIG list to have an appointment at...some point.
Normally its eaiser to have a smart meter installation booked if you don't have one already as its the quickest and fastest way to have the meter looked at/replaced with a new unit. In your case this is probably not an option as you have one already.
In 99% of situatioins there is never a problem, over 5+ years on the phones, I came across ONE actual problem with a very old gas meter, with hundreds of "complaints" from angry people who didn't accept there was nothing wrong from a trained engineer because they know better than people actually trained in the subject. You are reading FAR to much into it, trying to prove there is an issue.
The simple answer will be the calorific value that was used to make the calculatioon along with many other factors not easilly reproduced
From someone who had to take calls from people like yourself, please dont call, they have it bad enough with the complaints about the cost of living crisis and people complaining about the high costs thinking the agent on the other end is personally responsible that they are in debt. They don't need pointless calls on top of that.
Sorry about the aggressivness by the way, I had to speak to so many people over the years who just whined and whined about the meter recording more than they where using (which is virtually impossible nowdays) while smiling and nodding along in the hopes they didn't want to raise a complaint as then I would be stuck with them for weeks on end until an appointment was completed, then having to tell them there is nothing wrong.
The go to response would be if you think your meter is faulty, get a smart meter installed, which people didn't like to hear, they are paranoid already so think smart meters are evil and are information gathering devices to do....something outside of recording energy used.
You would then have the awkward manager call requests from people who just didn't accept the conclusion even though they have ZERO evidence of anything and having to justify the callback to your manager which was difficult most the time to get them to do it.
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On the subject of the accuracy of gas meters. In one of my previous jobs as a calibration engineer I use to work for a firm that specialised in gas flow. So I use to calibrate gas meters and the ones that are commonly found in some homes everyone I ever calibrated would read around 1% high.
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Ofgem do allow an agreed level of tolerance, from memory I think a meter can run up to 2% fast or 3% slow and is still considered to be accurate for billing purposes.
From memory +/- 2% tolerance on the household meters sounds about right. The supplier would most likely add a bit more to take into consideration tolerance uncertainties so 3% wouldn’t be unheard of.
Soldato
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Yes your meter is reading incorrectly