A cooker will generaly burn straight away but the air is following through and burning will extinguish when the air has reached the burner, that air then has to be purged until burning is re established.
It’s very easy, indeed one could say it’s a trivial exercise to purge when a cooker exists but what about the situation where there is a boiler sited in an understairs cupboard, with no other gas appliances in the property, where purging by disturbing pipework would result in gas in a confined place that cannot be ventilated by natural means. Leaving the pervading smell of gas isn’t acceptable for the customer. Burning off the gas by disturbing the gas connection at the boiler and igniting it could result in flame damage to the external wiring, the internal wiring, the condensate trap and the condensate drain pipework. Then you have to check for leaks with LDF. So is firing up the boiler, letting it self purge and accepting a failure to light several times in sequence with the risk of locking out, infinitely more preferable to any disturbance of the gas connection?
@@Михаиллеви tell me what’s wrong with it then? Why wouldn’t you tightness test (perhaps locally) if you disturb a gas fitting? Boilers are set purging. If you can’t tell me where I’m wrong then I’ll just assume you don’t know what you’re talking about.
Purge volume for any installations equal to or above 0.2m3 or with pipework greater than 28mm is, meter volume + pipe volume + 10% for fittings, multiplied by 1.5. Everything equal to or above 0.2m3 must be purged with a continuous source of ignition.
Hi MSK, this is very well known, but can't find a video actually showing how this is done in reality. Is there such a video, or could you do one Allen. It seems everyone just slackens a nut, smells gas then reseals???
@@davidb2464 here is an industrial one but they use air to gas ratio test equipment to ascertain that the purge is correct rather than an open burner. The amount of testing is insane. They even tightness test the purge equipment. XD th-cam.com/video/j5yIxN1vKMc/w-d-xo.html
This is incorrect. It's not 0.2 m^3, it's 0.02 m^3. You are out by a factor of 10. If you're going to quote figures, GET THEM RIGHT! Furthermore, it's not purge volume, it's installation volume (IV) that determines this.
paul bond I have thousands of questions to answer, I do try my best. Remember I am here for free to try and help people. Normally you would crack the nut under the boiler, try and control as much as possible. As always please refer to the gas manual for unto date advice. Happy New Year
@@AllenHart999 there’s a bird on you tube who just fires up the boiler don’t crack the nut on the boiler my point is why didn’t she crack the nut instead of firing the boiler she’s gas safe registered
Allen what about a vid on correct procedure on how to cut a branch into a gas line that is in use or already purged with gas in all the ACS courses and refreshers this topic was never touched upon
@@AllenHart999 Hi Allen, yep this would be very informative. I've just read that the meter has to be removed and all ends sealed with appropriate fittings. This has never been explained during traing or when done in reality? What is your experience of others actually doing this in practise?
If it’s a g4, u6 and e6 and under 28mm pipe work is it just up to 10 on the Meters or until the gas lights? Also if it’s over 28mm or g10 or u16 how much does it need to go up by at the meter mate?
A tip: don't say "10 on the meter". It's not ten, it's 0.010 m^3. If you have a meter with only 2 decimal places on the dial, then purging "10" will get you into serious trouble. Just grasp the nettle and become comfortable with using decimals.
1. Appliances won't light if the pipes are full of air 2. If there's an air / gas mixture in pipes, this is a dangerous (combustible / explosive) situation.
A tightness test has to be done BEFORE a purge. That's NOT the same as saying "a purge has to be done after a tightness test" - I did acs training last year, and never came across the idea that: "once you TT, you must purge". Are you sure about this?
Same here. When you take the test nipple off of a meter you hear gas escaping. You are told to attach your rubber hose quickly to stop air entering so where does the air get in the system to necessitate a purge every TT ?
What makes me laugh about `gas safe is . You cant leave a cooker purging and look at the gas meter . But you can walk away and leave someone with a gas leak if its within the parameters . Personally Id never left a job with a drop If it needed re piping it got it
There’s no parameters for a leak. The drops are suppose to be proven to be passing through the meter or appliances. I.e pipe work alone should never have a drop.
@@dando1898 its still a leak. Apparently if you tightness test old pipework and appliances and the drop is permissble and no smell of gas you can walk away yet the leak may be in the pipework
@@Михаиллеви its not as simple as walking away, if there is a leak then you have to investigate that leak, if the leak is on the pipework then you have to isolate that pipework because its ID or fix the leak, if its on an appliance and there is no smell of gas then it is taken that the leak is passing out the flue and not building up within the property, if there is a smell of gas then again the appliance is ID and needs to be isolated or fixed
Ok I just don’t have a time crunch lol lol I love it I just you u it was nice and you have the best for you yand to and get get you ready for the next Friday or Sunday I have a few things that I would love you to come see me you know what I’m going on te I love y’all you I know I have to a get get you I gotta go to work and I have a friend for a few weeks so I’m just trying to close the door I know I don’t know if I have to get it done but I just got started off with a few minutes of sleep and wow e I just don’t have to get it done with all my stuff I need you to go to sleep I’m so glad you have my
Cheers, Allen. Perfect complement to the Logic 5
Thanks very much for your comment, please consider subscribing to support the channel 🙂
This is great. Making the training manuals alot easier to understand.
Thanks all, it good to get a refresher
A cooker will generaly burn straight away but the air is following through and burning will extinguish when the air has reached the burner, that air then has to be purged until burning is re established.
Great, not complicated. Well explained.
Where does it say in the book we must purge after a tightness test? Say for instance doing a cp12
Good question. It doesn’t. Thanks.
Bloody hell its Russ , past tutor nice bloke
He is a good guy. Thanks for watching.
Very clear. Easy to understand. 👍😊
Great video💯
Glad you enjoyed
7:19 - I haven’t got my MET1, but is the electric socket too close to the meter?
25mm gap is enough. If the socket was a consumer unit then it would 150mm gap
It’s very easy, indeed one could say it’s a trivial exercise to purge when a cooker exists but what about the situation where there is a boiler sited in an understairs cupboard, with no other gas appliances in the property, where purging by disturbing pipework would result in gas in a confined place that cannot be ventilated by natural means. Leaving the pervading smell of gas isn’t acceptable for the customer.
Burning off the gas by disturbing the gas connection at the boiler and igniting it could result in flame damage to the external wiring, the internal wiring, the condensate trap and the condensate drain pipework. Then you have to check for leaks with LDF.
So is firing up the boiler, letting it self purge and accepting a failure to light several times in sequence with the risk of locking out, infinitely more preferable to any disturbance of the gas connection?
Excellent 👍 thanks so much for sharing video. Keep them coming. Also what manual do you use/recommend
Might be best to ask Viva that in the group. It will depend on what the training company use.
Hi al , do u just crack a nut under the boiler if theres no gas cooker ? Aslong as its well ventilated? And under control
No. If you do that you need to do a tightness test again. Just fire the boiler up, it should self purge
@@Matilda1337 really ? You tell your examiner that on an ACS assessment?
@@Михаиллеви tell them what?
@@Matilda1337 what you said in your comment
@@Михаиллеви tell me what’s wrong with it then? Why wouldn’t you tightness test (perhaps locally) if you disturb a gas fitting?
Boilers are set purging.
If you can’t tell me where I’m wrong then I’ll just assume you don’t know what you’re talking about.
Purge volume for any installations equal to or above 0.2m3 or with pipework greater than 28mm is, meter volume + pipe volume + 10% for fittings, multiplied by 1.5. Everything equal to or above 0.2m3 must be purged with a continuous source of ignition.
Hi MSK, this is very well known, but can't find a video actually showing how this is done in reality. Is there such a video, or could you do one Allen. It seems everyone just slackens a nut, smells gas then reseals???
@@davidb2464 there are some industrial installation videos I'm sure where they employ a burner for purging, but I haven't seen a domestic one.
@@davidb2464 here is an industrial one but they use air to gas ratio test equipment to ascertain that the purge is correct rather than an open burner. The amount of testing is insane. They even tightness test the purge equipment. XD th-cam.com/video/j5yIxN1vKMc/w-d-xo.html
This is incorrect. It's not 0.2 m^3, it's 0.02 m^3. You are out by a factor of 10. If you're going to quote figures, GET THEM RIGHT! Furthermore, it's not purge volume, it's installation volume (IV) that determines this.
What if the furthest applience away isn't a cooker? It's a fitting but the purge volume is greater than 0.02m³
you can purge from any appliance mate
If the furthest point is a condensing boiler but there is a cooker which would you use ?
Boiler
What about imperial meters with 35mm pipe. How is the purge volume assessed ?
If I turn the boiler on will that purge air out of the gas pipe 15mm between meter and boiler
Merry Christmas
@@AllenHart999 merry Christmas but you didn’t answer my question
Allen hart never replied to my question as much use as a hole in a bucket
paul bond I have thousands of questions to answer, I do try my best. Remember I am here for free to try and help people. Normally you would crack the nut under the boiler, try and control as much as possible. As always please refer to the gas manual for unto date advice. Happy New Year
@@AllenHart999 there’s a bird on you tube who just fires up the boiler don’t crack the nut on the boiler my point is why didn’t she crack the nut instead of firing the boiler she’s gas safe registered
Allen what about a vid on correct procedure on how to cut a branch into a gas line that is in use or already purged with gas in all the ACS courses and refreshers this topic was never touched upon
That is a great idea. I will add that on my list. Thank you.
@@AllenHart999 Hi Allen, yep this would be very informative. I've just read that the meter has to be removed and all ends sealed with appropriate fittings. This has never been explained during traing or when done in reality? What is your experience of others actually doing this in practise?
What book was that cheers
If it’s a g4, u6 and e6 and under 28mm pipe work is it just up to 10 on the Meters or until the gas lights? Also if it’s over 28mm or g10 or u16 how much does it need to go up by at the meter mate?
G4, U6 and E6 if pipework is under 28mm purge volume is 0.01, The purge volume for G10 or U16 is 1.5 X the installation volume.
A tip: don't say "10 on the meter". It's not ten, it's 0.010 m^3. If you have a meter with only 2 decimal places on the dial, then purging "10" will get you into serious trouble. Just grasp the nettle and become comfortable with using decimals.
@@Jehannum2000tip get a life you sad bell
why do you need to purge? I am not a gas engineer I am just interested to know. I find things like this very interesting
1. Appliances won't light if the pipes are full of air
2. If there's an air / gas mixture in pipes, this is a dangerous (combustible / explosive) situation.
A tightness test has to be done BEFORE a purge.
That's NOT the same as saying "a purge has to be done after a tightness test" - I did acs training last year, and never came across the idea that:
"once you TT, you must purge".
Are you sure about this?
Same here. When you take the test nipple off of a meter you hear gas escaping. You are told to attach your rubber hose quickly to stop air entering so where does the air get in the system to necessitate a purge every TT ?
How do you continually Apply ignition when its not hot plate?
Did you ever find out the answer to this I'm a little confused
Thanks for these Al I got my acs coming up soon brickin it
Nothing hard about it really. You get all the books with the answers. 👍
What does commissioning mean?
We will do a video on it. Thanks.
@@AllenHart999 cant wait
Alternative Facts To bring something (ie a gas appliance) into working condition.
Hia bud, any information on where I could obtain one of these books that Russ was using? Many thanks!
Thanks for that Russ..👍
No problem 👍
I thought you only purge from furthest appliance
What makes me laugh about `gas safe is . You cant leave a cooker purging and look at the gas meter . But you can walk away and leave someone with a gas leak if its within the parameters . Personally Id never left a job with a drop If it needed re piping it got it
Thanks for the comment.
There’s no parameters for a leak. The drops are suppose to be proven to be passing through the meter or appliances. I.e pipe work alone should never have a drop.
@@dando1898 its still a leak. Apparently if you tightness test old pipework and appliances and the drop is permissble and no smell of gas you can walk away yet the leak may be in the pipework
@@Михаиллеви its not as simple as walking away, if there is a leak then you have to investigate that leak, if the leak is on the pipework then you have to isolate that pipework because its ID or fix the leak, if its on an appliance and there is no smell of gas then it is taken that the leak is passing out the flue and not building up within the property, if there is a smell of gas then again the appliance is ID and needs to be isolated or fixed
The purge volume is thr minimum not the maximum as stated here.
Why not show us on something other then hobb?
Can barely hear you
Ok I just don’t have a time crunch lol lol I love it I just you u it was nice and you have the best for you yand to and get get you ready for the next Friday or Sunday I have a few things that I would love you to come see me you know what I’m going on te I love y’all you I know I have to a get get you I gotta go to work and I have a friend for a few weeks so I’m just trying to close the door I know I don’t know if I have to get it done but I just got started off with a few minutes of sleep and wow e I just don’t have to get it done with all my stuff I need you to go to sleep I’m so glad you have my
What the hell are you talking about!!!!!!!