GAS PRESSURES PART 1, a gas tutorial all about standing, working and operating pressures for ga.s.
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- Опубліковано 30 чер 2024
- Derek in part 1 shows trainee gas engineers what working, standing and operating gas pressures at the meter and appliances are.
Another amazing video Derek, don't know why they've changed working pressure to operating pressure confusing our little brains. 😂😂, this was a brilliant video & well presented like always whether its in the classroom with you or watching you on videos you're always the top Tutor.. 👍👍😀😀
This bought back memories...I did my Indentured Gas Apprenticeship in the 1960s when we still had "town gas". In those days the apprenticeship was from leaving school at just 15 to 21, almost 6 years. But, in those days we learned everything about gas, from how gas was made, how it was distributed throughout the district gas mains, how and why gas holders were built. etc, etc... It was a great apprenticeship, taught me well, and gave me a good living... oh, and it was quite common to get a clip round the ear off your fitter if you gave him some lip... Great times.
You are a legend! Thank you so much and very appreciated.
You are actually extremely helpful and clear on explaining. Everything spot on.
thank you DEREK FOR YOUR GREAT SERVICE ,GREAT TEACHING
Thank you Derek, like always I really enjoyed your videos, the explanation very clear
I think I’ve watched nearly all of your tutorials I now fully understand what you are saying keep up the good work and keep them coming Derek kind regards Tony gaunt🤗
You are such an incredible technical instructor. You’ve assisted most of us initial assessment understanding the practical know how to the industry.
As allways absolute amazing mate ✌️👍😊well explained !never seen a better trainer !!you have the German in you 😘Connor
Great video , I was a bit confused before watching the video about the Permissible Drop but now I'm fully understood , Thanks Derek
Great video on tightness testing and pressures at the meter very clear thanks.
Always top videos off Derek
What a legend. Thank you for sharing your knowledge
You are a very good teacher.. down to basic and then you build up knowledge for learners to understand.Thank you
Very informative video. Thanks Derek 👍😀
Brilliant video derek. Revising for my Initial assessments. Thanks for giving us the understanding of not just carrying out standing & operating pressure but to understand why we have these figures in place i.e 21+-2. Trainee at tomkat gas training center. 🙂
Good video for proper understanding let by and all test thanks Tom
Outstanding video so clear and the details are perfect
It's finally printed into my brain
You deserve more commendation for your work 💪
Derek your a legend keep the vids coming!
Great video...thanks Derek.
Always brilliant derek
Really injoy watching easy to understand thanks keep the good work up
I am indeed very grateful for this explanation
Thank you for all your videos derick
GREAT STUFF DEREK THANKS
great !!! well explained , Tom good job
explained in easy steps. thanks Tomkat
Excellent video 👍
Great video, thank you 👍
...a great video Derek. Keep up the amazing videos you take the trouble and time to make. Just to give you some insight as to why they have changed 'working pressure' to now 'operating pressure. I know this video is I guess over two years since you made it, bvut I have just come across it now. That is'enough of the waffling, lets get right into it' as you say.
1. Working pressure:
Well, working pressure is not a 'dare I say' a 'standard' . Unless ofcourse 'all' appliances were made to 'operate' at a specific given @ Rate of figure. Design, materials, size, etc will no doubt differ from for a start manufacturer to manufacturer as well as country to country.
Operating pressure:
So they rightly come up with the term 'operating pressure'.. This can now be used as a means of 'standard', covering all types of appliances as the manufacturers have stenciled the 'working/operating' pressure on the unit.
2. Standing pressure
The 'standing pressure' is there as a form of supply and demand. Just to illustrate , lets bring in a water/shower pump. Say I connect up the water pump to the water Mains supply and Not an Overhead water Tank ! What will happen ? Depending on the regular 'usage', the pump will burn out , and that is within say 1 week. If you are lucky maybe 2 weeks. Why is that? It is because the 'standing' pressure is not meeting the 'operating' pressure of the pump. So the pump manufacturers as part of their design have used the 'standing' pressure as part of the formula to manufacture their different pumps. But the 'standing' pressure is Not the water Mains supply, but a water Tank. This will ensure there is enough water to meet the 'standing' pressure for that particular water pump. Hope my waffling helps. lol
Clear Explanation on every thing regarding pressure, thanks Derek! ‘Bilal M’ trainee tomcat.
These videos are so helpful sir
Great video on tightness testing and pressures at the meter. Everything explained nicely and easy to understand. From now on I will try to refer to working pressure as operating pressure!
Does anyone else take ages filling a u-gauge with water and trying to level it at zero and get soaked whilst doing it or is it just me 🤣. Thanks Derek 👍🏻
Asian Jon. Training.
Just you mate 🤣🤣😜👍🏻
Most def just you mate 😂
Thank you Derek.
Excellent video 5*
Never knew why it had to be 19-23.. I do now. Thanks for plugging another wee gap in my knowledge.
Used to be 20-22 until National Grid/BG got fed up of being called out to 19 and 23 mb working pressures
Very simple explanation pal 👍
You the man bro..👍
Thankyou Derek
Thanks again Derek for sharing this helpful information with us it’s been very easy for me to understand that, also wondering where to getting a U_gauge like you’re using it in this video 🙏
I get our u gauges from BES but most plumbers merchants or eBay sell them
Excellent 🌹
Thanks a lot darek
Very good and appreciated
Now if you can make some video on Regulations, ID,At Risk,responsibility of Landlord, Gas suppliers, and engineers,
Thank you Derek
Bless you 🙏
All ready have check out my channel you will find them there
I hope i will learn too Derek
Great vid again Derek 👍 Aaron j trainee 😁
Yes, you did say that if you have a drop you then test the carcass whcih is allowed a zero drop. This basically means the drop allowance is on an appliance that is fitted. (assuming no smell)
Ray Hurrell brilliant
thanks for good explin and show how to do test working test and standing test
Many thanks
It’s for me I have requested Sir thanks
Great video as usual, could you please explain the following in your next video:
Why is any MB drop allowed on appliances, it’s a gas leak!
What is the correlation between type of meter and size of MB dropped allowed.
Again great channel. 👍👍
Have you not Sean my video on gas meters? More information coming on Wednesday so look out for that 👍🏻
Thank you, Nikola Ditsov
Great video again thanks . Are you planning to do videos on chimneys ( a long and interesting topic...)
In the works 👍🏻
Thanks.
Thanks again, great video. For operating pressure at meter, would you put all appliances on maximum at same time if you have more than one in property, say a boiler and cooker. Or just one appliance at a time? Thanks
All will be reviled on Wednesday in part 2 😁👍🏻
@@tomkatgastraining bring it on
Thanks on to part 2 now
👍🏻
Thanks you 🙂
Thanks
Great content Derek can u just ask if the operating pressure at the meter is wrong what action would you take? And what would cause it? Thankyou.
You would get in touch with Cadent because it could be poor gas pressure or broken regulator
Tanx for the upload plz if you could can you do fault finding on combi boilers,tanx
Take a look at my videos called inside a boiler case they show lots of of information on fault finding
@@tomkatgastraining tanx topman tamkat👍
👍👍
❤
If a six ring cooker do you put on 5 rings to get operating pressure
Derek great video.
Since this video was posted there has now been a small change the operating pressure is now from 18.5mb - 23mb. Dont know why?
I have done a video on it have a look on the channel for it 👍🏻
👍🏼
Ali 👌👌👍👍
Hi, when doing working pressure for the cooker, wouldnt you need to put the oven on full rate also?
Nope just the 3 biggest hob rings
Derek, I have the following question: if I have a let by 5mbar/min and leak of 5mbar/min (for example) would I ever find out and how?
Well that would be very unlikely and very unlucky if you did. I would expect a report smell of gas if you had a 5 mbar drop.
Are you allowed to leave the u gauge attached to the meter unattended when you go and start up the boiler to check working pressure?
As long as it is stable and not going to fall over yes you are
I’m just an interested viewer, ( ex industrial process operator) regarding the U tube manometer, when would their be an occasion when one side scale reading be a different reading than the other side ?
When it hasn’t been zeroed correctly or not level
thanks. if you zero the u gauge then wouldn't the readings always be the same either side? what's the point in doing the calculation of bother sides ÷2 if both sides are the same?
If you have ever done it you will find it normal for them to have different readings
👏🏻✅
I don't understand why they say add the two (water gauge) readings together and divide by 2. As long as you have zero'd the meter prior to any test the readings will be identical on either side - so you can just go off the positive side on the LHS. Just seems to be complicating matters. They should state you always zero the meter prior to any test ! I think its just making it confusing by adding the extra arithetic....
Question, when you are performing the pressure test on the ECV, how do you know that it is the ECV that is at fault and not another part in the system?
ps thank you for video!
If you can tell if the boiler is work how much i have read gas in gage that mean drop thanks
Good video well done 👍
What is the difference between working pressure and operating pressure?
Nothing they are the same thing 👍🏻
@@tomkatgastraining thank you that’s what I thought just wanted second opinion 👍
👍🤓👍
@Derek, in Gas college they always told us the first thing you do before testing is using a volt stick on the meter on the anaconda I believe. no gas engineer ever does it though lol, do they have a point? is it uk reg? I think one in a million engineers got shocked or something one day
Yep they are correct it’s not law but is best practice it’s for your own safety
Yeah, it’s probably best practice but your video is to show us how do the tightness test and it is very informative, thanks for your videos, you’re doing great work.
👍 Sue Warrington
Thanks. Why is it the case a drop is allowed with existing appliances connected? I may be completely stupid, but a drop is a drop no? Gas is escaping. Isn't that a problem? The wording the books and everyone uses seems to confuse things. Plenty of engineers seem to think if there is a drop on an existing system with old appliances and its within range then that's ok. Even the books don't explicitly make it clear that if you test with appliances on you have to ensure the the drop is on the appliance by isolating the appliance. The books split criteria for pipework into new and existing when really they should just say no drop is allowed and if you find one you have to ensure it's on the appliances.
So can i clarify pls. Working pressure/operating pressure is taken at the actual appliance and also the meter and allowed a drop of 1mb?
Also what is the difference between a let by test and standing pressure? Surely in a letby your testing the section of pipe all the way from the ECV and throughout all the pipework up until the appliances in the house(so just the pipework in system with all appliances off).surely this area being tested is exactly the same in the letby and the standing pressure test?
let by test is testing the ECV to ensure it's working correctly when closed and isn't letting gas past it.
Temperature stabilisation allows the gas pressure to stabilise before the tightness test.
Tightness test is a test to ensure that there is no escape of gas from the installation downstream of the ECV and the installation is gas tight.
Standing pressure test is to see what the standing pressure of the installation is and indicates whether or not the meter regulator is working.
Working pressure, now renamed as Operating Pressure, is done both at the meter, and then at the appliance, to ensure that there is not more than 1mbar of pressure drop between the two when the appliance is running at full capacity (the exception being a cooker hob).
working/ operating pressure is the same thing.
@@UndisputableFact surely standing pressure would/should be the same at the meter as at an appliance? If gas has nowhere to go because no leaks and no appliances are running then surely the pressure would be evenly distributed throughout pipework?
@@Benji-gq9gx yes standing pressure will be the same everywhere in the installation while no appliances are running.
@@UndisputableFact thanks
Do you do standing pressure then working inlet and burner (if not zero gov)
Just because I’ve seen another UA-camr day do working then standing
You can do it in any order you like because each test isn’t affected by the others.
@@tomkatgastraining thanks for reply
Have you covered any chimney/flue vids?
@@lostinthoughtscalminsilenc8167 ua-cam.com/video/jE3XUmpJVzo/v-deo.html that’s part 1 of 2
@@tomkatgastraining any idea when you’ll do part 2. Your videos are my go to for revision as you explain really well
When doing working pressure do turn all appliances on? Or is that on if when testing inlet?
You have to have a minimum flow rate through the meter of 0.5m3 to a maximum of 3.5m3 for working at the meter but at the appliance it’s just that appliance running
@@tomkatgastraining so only test working pressure with each appliance on highest setting?
@@lostinthoughtscalminsilenc8167 working pressure at the meter can be done with all appliances running as long as it doesn’t exceed the maximum flow rate or just one as long as it’s not less than the minimum
@@tomkatgastraining okay great thanks
17:40 A gas flow rate of 3.5 m3/h should give you (3.5/0.095=36.8) 36.8 kW.
A minimum gas flow rate of 0.5 m3/h should give you (0.5/0.095=5.3 ) 5.3 kW.
I think they should just get rid of allowable drops on domestic as once you disconnected everything and see the hobs leaking 3mb who really re connects it and what customers ever say ok Hob leaks gas but it’s fine!
if you have proven that the leak is not on the pipework and the appliance is correctly sited and the room is adequately ventilated and there is no smell of gas then it should never reach a point where you have an immediately dangerous situation as there will never be an explosive mixture, some companies do have a zero tolerance approach to any gas leak regardless if its on an appliance. What gas engineer is going to feel good about leaving a 3mb drop on an appliance, hardly any, but British standards allow for it.
If there’s excessive gas pressure at the appliance what impact would this have?
The only way you can get excessive pressure at an appliance is when the meter regulator has failed and this could lead to an ID situation.
Tomkat 👍🏻
Chris tanker 👍
17:55 MOP: meter operating pressure
Nope it’s maximum operating pressure
CH 👍
Why test the standing pressure and is there actually a requirement to do so?
Please let me know if I’m wrong, but I was always under the impression the meter governor operated whilst gas was flowing through it-not whilst standing.
The standing pressure is a test to prove the regulator is working and how much gas you have. It’s one of those tests gas engineers don’t do because they think it’s not necessary. All the tests are there for engineers to determine if the installation is safe so if an engineer thinks there are no problems with the incoming supply then no need to do standing pressure.
@@tomkatgastraining thanks for your response.
I thought “operating” (working) pressure is the test that proves the regulator is working correctly? Not the standing pressure. I’m sure the regulator only “regulates” when gas is flowing through it not whilst “standing”?
@@mattl9702 because you can have up to 75 mbrs on low pressure and up to 2 bar on medium pressure the standing pressure shows you if the regulator is regulating it down when the appliances are not running. It also shows when you have low incoming pressure.
@@tomkatgastraining So the regulator reduces pressure from ~75mbar to what pressure? Not trying to be a clever clogs, I’m curious.
The reason I ask-I once got into a big debate with Transco years ago over the same subject. I was arguing the “standing pressure” seemed too high on a domestic property. To cut a long story short they disagreed and told me the working pressure was fine therefore all was ok. I’ve never tested the standing pressure since-that was roughly 20 years ago!
@@mattl9702 the regulator has 2 tests to see if it’s working which as you know are standing and working pressure. You can get a regulator working at 23 mbrs but if you leave it when the appliances are off it could rise to over 30 mbrs if the regulator is passing. As you know most gas engineers don’t care about standing and working pressure at the meter but as a trainer I have to show my trainees the correct procedures for testing safety devices and with a regulator being also classed as a safety device I have to show the correct testing methods.
Hi mate, when doing inlet at boiler and combustion. If I’m using a fga can I use them at the same time? Would I just isolate the gas put my probe in and attach my hose to inlet then put boiler to max and turn gas back on?
Not really sure what you are asking but inlet pressure is done with heating and hot water not high and low. High and low rates are for fga unless the boiler manufacturers say so
@@tomkatgastraining so you’re saying when doing inlet it does not need to be on high?
My boss does them both at the same time? So I was just asking how I could do that? Would I just isolate gas put hose on inlet and probe in flue and put to full rate? As I use fga as a pressure guage
@@lostinthoughtscalminsilenc8167 depends on the equipment you use. I just do them separately
@@tomkatgastraining okay np, but when you do inlet you isolate gas first right?
Is it bad if I can’t find where inlet is I don’t isolate the inlet so I can’t find where gas is coming out of then I isolate and put hose on?
If not how else can you find where it is? 🤣
Hello sir I have one question....,,
There is a imperial meter ,but can find type on it what means that ????
Is it G4 u6 E6 what type of meter is it ??
Yes the number is the type of meter the imperial is a u6 meter or a u16
How can you have 23 mb (standing P) when the regulator is set to cut off at 21 mb ?
differential manemometer or u guage but?? do you know the difference?
I know the difference but can you spell it. What are you getting at I have no clue what you are on about 🙄
tomkat👍
what is the lowest working pressure you can have at meter outlet at peak demand?
It’s shouldn’t go below 19mbrs but Cadent engineers are told it can go as low as 15mbrs if the safe operation of the appliances are not affected in peak demand
@@tomkatgastraining Yes because there is an allowable 4mb drop across the meter installation at peak demand (BS 6400-1 6.2 for pressure absorption) which means that conceivably you might have something as low as 14mb inlet working pressure at the appliance, crazee! :D
@@MSKChess it dose say 15 Mbrs as minimum is 19 mbrs minus 4 is 15 working at the meter but also says this would only happen if pipe work is undersized for the appliance but like you say crazy 👍🏻
@@tomkatgastraining yeah in the notes it assumes one millibar drop for pipework, so four for the meter and one for the pipework giving 14 millibar at the appliance inlet. Maybe a Vokera I think can safely run as low as 14mb, but those big Worcester boilers require at least 18mb according to MI's. XD
btw I know you guys are a training establishment but do you do breakdowns? some vids on fault finding would be awesome, your fan MSK XD
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