gas supply to combi
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namsag
Ok chris stand by the courage of your convictions and during your next yearly insection take the guy to a boiler that is repaired like that and see if he allows you to let it go. A simple phone call to corgi would put this right .Regs don`t change a lot over the years but what does is how they are interpretted and as corgi are constantly dealing with these regs and queries you will find the interpetation of those has changed and also often more than one reg applies to same situation . Simple question in regards to how regs effect a job can a hob be fitted on any sort of flex . i will give you the corgi answer
Oilski that's what I'm saying. Even the original short version said he needs a replacement case. By managing/monitoring the repair the risk in practice is zero. So why do it? I think it's the best thing to do. Commercial reasons. By keeping the boiler going and the family warm until the boiler or the part is replaced you get the job. If the property were empty there would be no point certainly.
Namsag I HAVE given you the Corgi answer.
Not that corgi make the law, so you are at liberty to disagree with it. Neither do they create a law by a particular interpretation - that is not in their remit. They can refuse membership of course, but we know they don't for doing something safe but NCS.
How many boilers have you installed using an existing gas line with just over 1mbar drop? What would you do if you found one??
Simple question in regards to how regs effect a job can a hob be fitted on any sort of flex .
Simple answer last time I looked a few years ago. And I don't think the BS (which I have) has changed. You basically should follow the manufacturer's instructions, though of course those are never complete. Iirc it says you cannot use a flexy hose unless you can guarantee that the hose will not be subject to more than 70 C AND that that proviso is also in the MI. Saw it on one, once. BUt if you decided to use a stainless steel flexy hose of the type used for commercial installations and followed the appropriate procedures for it , corgi would have abloody hard time convincing anyone including a Judge that your installation failed to satisfy all requirements.
If anyone says that all appliances must be installed srictly in accordance with MI he's being too simplistic and is strictly wrong. You use fixings other than those provided, maybe drilling an extra hole or two in the bracket, if you deem it necessary. Your decision, your risk. Same with the cooker hose. And the patch over the hole.
Wot about my questions in my previous answer?
One for you: How many boilers have you installed using an existing gas line with over 1mbar drop? What would you do if you found one??
On my last inspection I took the guy to a LGSR on a Profile with a corroded cast aluminium terminal. All the horizontal bars on the end of the centre tube had gone. One of the fixings had dropped out so had been replaced with a nut bolt and washer a bit bigger. FGA OK. NCS - which I already had checked with corgi, because I thought it might be AR. He made sure I put it on the right form , NCS.
Namsag I HAVE given you the Corgi answer.
Not that corgi make the law, so you are at liberty to disagree with it. Neither do they create a law by a particular interpretation - that is not in their remit. They can refuse membership of course, but we know they don't for doing something safe but NCS.
How many boilers have you installed using an existing gas line with just over 1mbar drop? What would you do if you found one??
Simple question in regards to how regs effect a job can a hob be fitted on any sort of flex .
Simple answer last time I looked a few years ago. And I don't think the BS (which I have) has changed. You basically should follow the manufacturer's instructions, though of course those are never complete. Iirc it says you cannot use a flexy hose unless you can guarantee that the hose will not be subject to more than 70 C AND that that proviso is also in the MI. Saw it on one, once. BUt if you decided to use a stainless steel flexy hose of the type used for commercial installations and followed the appropriate procedures for it , corgi would have abloody hard time convincing anyone including a Judge that your installation failed to satisfy all requirements.
If anyone says that all appliances must be installed srictly in accordance with MI he's being too simplistic and is strictly wrong. You use fixings other than those provided, maybe drilling an extra hole or two in the bracket, if you deem it necessary. Your decision, your risk. Same with the cooker hose. And the patch over the hole.
Wot about my questions in my previous answer?
One for you: How many boilers have you installed using an existing gas line with over 1mbar drop? What would you do if you found one??
On my last inspection I took the guy to a LGSR on a Profile with a corroded cast aluminium terminal. All the horizontal bars on the end of the centre tube had gone. One of the fixings had dropped out so had been replaced with a nut bolt and washer a bit bigger. FGA OK. NCS - which I already had checked with corgi, because I thought it might be AR. He made sure I put it on the right form , NCS.
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namsag
None is the answer chris and the reg is the pipework must be designed to ensure the maximum pressure loss to each appliance does not exceed 1mbar when subjected to maximum load. So one of the first things i would do on repping a job is make sure this is achieved secondly if it isn`t i would check meter working pressure is correct if it wasn`t i would call transco to reset(even though i have reset thosands in my time). I would then include price of pipework upgrade into job with the provision that if i could get rid of any elbows etc from existing layout to achieve proper drop price would be altered accordingly.
Wot about my questions in my previous answer?
One for you: How many boilers have you installed using an existing gas line with over 1mbar drop? What would you do if you found one??
None.
as namsag says you should be checking for this prior to giving a quote so when you send it out it includes upgrading the supply as well.
Must say I have only lost a job or two to other companies because of this. I would not want to work for someone who wants a half arsed job so **** em
One for you: How many boilers have you installed using an existing gas line with over 1mbar drop? What would you do if you found one??
None.
as namsag says you should be checking for this prior to giving a quote so when you send it out it includes upgrading the supply as well.
Must say I have only lost a job or two to other companies because of this. I would not want to work for someone who wants a half arsed job so **** em
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namsag
I will just add this chris customers can be the biggest fibbers out there ,and your main point about carrying out a repair such as that is it can be monitored to check it`s integrity and it`s getting the customer warm till boiler is changed . Who says they are going to let you back in to check it and change boiler at a large cost to them if they think it`s ok.. When i worked for BG it`s amazing how many people called you out on emergencies (gas leaks /fumes) only to threaten you with violence and try and throw you out the house and try to stop you doing your job which was to save there lives because it would cost them a bit of money or leave them cold for a day or so.Customers can be the strangest people and the nicest.
"your main point about carrying out a repair such as that is it can be monitored "
That isn't what it says on my screen - now you're imagining things!
Obviously nobody would trust an unknown customer, it would just add a bit of pressure. Non-compliance easily dealt with by a recorded delivery letter referring to written agreement, (as with aspects of LGSR's - standard stuff).
"the reg is the pipework must be designed to ensure the maximum pressure loss to each appliance does not exceed 1mbar when subjected to maximum load. "
If you're going to quote regs at me mate, you'd better get them right. You got this one wrong. Do you wish to be taken seriously? Off you go and check it.
"you should be checking for this (1 mbar drop) prior to giving a quote "
Perfectly bleedin obvious thankyou if there's a working boiler there wth the same gas rate as the new one. But how often does that happen? Maybe one in five.
So if you change a boiler and find a 1.1 mbar drop you disable the boiler until you've ripped the laminate floor up if there's no option on pipework elsewhere. I thought you'd say that. You think it's "to save there lives" ? ( I assume you meant "their"). I think that would be rather daft.
Remaining question still unanswered: You find an installation with a (say) 1.1 mbar drop because the pipework is undersized - what do you do about it?
(Easy to measure, by the way dear reader not familiar, with digi meters resolving to 0.01mbar)
And what was the point of the question on the flexy hose??
That isn't what it says on my screen - now you're imagining things!
Obviously nobody would trust an unknown customer, it would just add a bit of pressure. Non-compliance easily dealt with by a recorded delivery letter referring to written agreement, (as with aspects of LGSR's - standard stuff).
"the reg is the pipework must be designed to ensure the maximum pressure loss to each appliance does not exceed 1mbar when subjected to maximum load. "
If you're going to quote regs at me mate, you'd better get them right. You got this one wrong. Do you wish to be taken seriously? Off you go and check it.
"you should be checking for this (1 mbar drop) prior to giving a quote "
Perfectly bleedin obvious thankyou if there's a working boiler there wth the same gas rate as the new one. But how often does that happen? Maybe one in five.
So if you change a boiler and find a 1.1 mbar drop you disable the boiler until you've ripped the laminate floor up if there's no option on pipework elsewhere. I thought you'd say that. You think it's "to save there lives" ? ( I assume you meant "their"). I think that would be rather daft.
Remaining question still unanswered: You find an installation with a (say) 1.1 mbar drop because the pipework is undersized - what do you do about it?
(Easy to measure, by the way dear reader not familiar, with digi meters resolving to 0.01mbar)
And what was the point of the question on the flexy hose??
point is you get the job away
so all you clever gits
please com and live in the REAL world
so all you clever gits
please com and live in the REAL world
I don't know all the regs, perhaps I got it wrong?
I can only remember the figures (in the table for pipe drops) being quoted to 2 sig figs, ie nearest 0.01 mbar up to 1 mbar and then 0.1mbar.
Sorry you'll have to tell me which reg are you referring to?
(I'm sure you're not thinking of the <0.3mbar figure, which of course is for tightness testing not drops in pipes.)
I can only remember the figures (in the table for pipe drops) being quoted to 2 sig figs, ie nearest 0.01 mbar up to 1 mbar and then 0.1mbar.
Sorry you'll have to tell me which reg are you referring to?
(I'm sure you're not thinking of the <0.3mbar figure, which of course is for tightness testing not drops in pipes.)
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namsag
Chris didn`t realise it was a spelling and gramma test. As for checking it try looking in section 5 page 77 last paragraph of the corgi handbook and you will find this is what it says. so if you have one off you go and check it. As for monitoring it,you said a reinspection and review in a short while maybe req is that not monitoring job. Also who says customer would respond to a letter. Now that would be an interesting conversation to transo "can you go round and turn off the gas to a customer thats refusing me entry to a boiler i have left in a dangerous condition". Original question was answered i said correct size of pipe or existing layout altered to give correct pressure.
Come on girls - we're getting to the 'Handbags at dawn' stage here.
Any regs have to be written assuming a level of competence for the people using them - ie. RGIs.in this case. It was decided at least 30 years ago that 20 millibars would be a 'satisfactory' working pressure for gas appliances and ever since manufacturers, Transco, RGIs & Uncle Tom Cobley have all worked to that figure.
But....
- the standard pressure gauge (manometer) used throughout the industry can only resolve to 0.5 millibar, so measured pressures are permitted to vary + or - 1 millibar.
- when you have MECHANICAL devices regulating pressure, variation is INEVITABLE, especially when conditions chage rapidly. So when a meter governor suddenly experiences a pressure drop due to a bloody great combi starting up, it's response to increase flow and raise pressure again is NOT instantaneous. Can't be. And anyway, you don't want a burner lighting up instantly at full burner pressure. So boiler ignition systems are SPECIFICALLY DESIGNED to cope with this, eg. by 'soft start' in the boiler gas valve.
- I sympathise with Chris: there's always the temptation to work to the limit of your own knowledge and competence. But in the case of working pressure on appliances, allowing it to remain 'wrong' is too risky because it allows too many others off the hook - Transco, boiler manufacturers,....
I KNOW perfectly well that there is NO actual 'safety issue' if the WP is 18 and the maximum burner pressure on the particular appliance is (say) 8, with a Honeywell gas valve that has an internal pressure drop of about 2 millibars. I mean - what could ACTUALLY happen? But the book says 20 +/- 1 and that's the required number. Having said that, what do you do when you ask Transco to raise the WP from 18 to 20 when the cause is low pressure in the street main and they 'can't' or 'won't'?
Any regs have to be written assuming a level of competence for the people using them - ie. RGIs.in this case. It was decided at least 30 years ago that 20 millibars would be a 'satisfactory' working pressure for gas appliances and ever since manufacturers, Transco, RGIs & Uncle Tom Cobley have all worked to that figure.
But....
- the standard pressure gauge (manometer) used throughout the industry can only resolve to 0.5 millibar, so measured pressures are permitted to vary + or - 1 millibar.
- when you have MECHANICAL devices regulating pressure, variation is INEVITABLE, especially when conditions chage rapidly. So when a meter governor suddenly experiences a pressure drop due to a bloody great combi starting up, it's response to increase flow and raise pressure again is NOT instantaneous. Can't be. And anyway, you don't want a burner lighting up instantly at full burner pressure. So boiler ignition systems are SPECIFICALLY DESIGNED to cope with this, eg. by 'soft start' in the boiler gas valve.
- I sympathise with Chris: there's always the temptation to work to the limit of your own knowledge and competence. But in the case of working pressure on appliances, allowing it to remain 'wrong' is too risky because it allows too many others off the hook - Transco, boiler manufacturers,....
I KNOW perfectly well that there is NO actual 'safety issue' if the WP is 18 and the maximum burner pressure on the particular appliance is (say) 8, with a Honeywell gas valve that has an internal pressure drop of about 2 millibars. I mean - what could ACTUALLY happen? But the book says 20 +/- 1 and that's the required number. Having said that, what do you do when you ask Transco to raise the WP from 18 to 20 when the cause is low pressure in the street main and they 'can't' or 'won't'?
Sorry but the sentence:
"As for checking it try looking in section 5 page 77 last paragraph of the corgi handbook and you will find this is what it says"
doesn't make sense.
Not a spelling test but you need to use the right words to make yourself clear.
I guess you might be referring to ""the reg is the pipework must be designed to ensure the maximum pressure loss to each appliance does not exceed 1mbar when subjected to maximum load. "
If that's what the corgi book says, then it's drivel, as anyone with half a brain can see. The truth is that the pipework must ACHIEVE a drop less than 1 mbar. The design is irrelevant. In Kev's real world we all know you don't necessarily get anything like as low a drop as the book predicts.
If you're going to quote regs OR make statements, you gotta get it right instead of ballsing it up all the time.
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The situation, as I have explained, is not dangerous.
The letter would not need to be answered. I'm not going to explain the obvious here.
Except that your silly suggestion of the call to Transco just makes you look just that.
Re the "what would you do if you found underpressure due to undersizing" I assume your answer is
"Original question was answered I said correct size of pipe or existing layout altered to give correct pressure."
I already reasked "suppose there is no option but to take the floor up"
Presumably you would take the floor up .
But I asked "suppose you find one" eg. on a Landlords Gas Safety Record. I suggest that you would not rip the floor up if you wanted to stay in business. So you ballsed it up again.
You presumably don't know the textbook course of action. Which if you look carefully enough is to declare the appliance AR. NOT NCS even if the flame picture is not altered. (specifically it's AR if the low pressure is due to undersized pipework)
That would cover half the appliances I see, but I only declare them NCS. I think that reg is unreasonable, and I ought to write to the powers to say so, but I'm not that good. I've only had half a dozen corrections made to the corgi handbooks.
CroydonCorgi has gone on to what would have been the next imponderables - Transco gaurantee 14mbar, appliances need 20, which you wouldn't even get with 20mbar at the meter, etc etc.
I agree , Namsag you have to live in the real world. IF you insist on quoting and "regs" all the time then keep ballsing it up, I suggest you stop before you dig a bigger hole for yourself.
And the more you try to stand up for regs which defy common sense when taken literally, the deeper you get.
And if you come back with another silly suggestion I'll fill thebloody hole in.
The cynical old beggars I was referring to way back are the ones who for example, justify leaving compression joints under floors because they "know how to make "and theirs "don't leak".
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"so measured pressures are permitted to vary + or - 1 millibar. "
ummm, no comment!
"As for checking it try looking in section 5 page 77 last paragraph of the corgi handbook and you will find this is what it says"
doesn't make sense.
Not a spelling test but you need to use the right words to make yourself clear.
I guess you might be referring to ""the reg is the pipework must be designed to ensure the maximum pressure loss to each appliance does not exceed 1mbar when subjected to maximum load. "
If that's what the corgi book says, then it's drivel, as anyone with half a brain can see. The truth is that the pipework must ACHIEVE a drop less than 1 mbar. The design is irrelevant. In Kev's real world we all know you don't necessarily get anything like as low a drop as the book predicts.
If you're going to quote regs OR make statements, you gotta get it right instead of ballsing it up all the time.
----
The situation, as I have explained, is not dangerous.
The letter would not need to be answered. I'm not going to explain the obvious here.
Except that your silly suggestion of the call to Transco just makes you look just that.
Re the "what would you do if you found underpressure due to undersizing" I assume your answer is
"Original question was answered I said correct size of pipe or existing layout altered to give correct pressure."
I already reasked "suppose there is no option but to take the floor up"
Presumably you would take the floor up .
But I asked "suppose you find one" eg. on a Landlords Gas Safety Record. I suggest that you would not rip the floor up if you wanted to stay in business. So you ballsed it up again.
You presumably don't know the textbook course of action. Which if you look carefully enough is to declare the appliance AR. NOT NCS even if the flame picture is not altered. (specifically it's AR if the low pressure is due to undersized pipework)
That would cover half the appliances I see, but I only declare them NCS. I think that reg is unreasonable, and I ought to write to the powers to say so, but I'm not that good. I've only had half a dozen corrections made to the corgi handbooks.
CroydonCorgi has gone on to what would have been the next imponderables - Transco gaurantee 14mbar, appliances need 20, which you wouldn't even get with 20mbar at the meter, etc etc.
I agree , Namsag you have to live in the real world. IF you insist on quoting and "regs" all the time then keep ballsing it up, I suggest you stop before you dig a bigger hole for yourself.
And the more you try to stand up for regs which defy common sense when taken literally, the deeper you get.
And if you come back with another silly suggestion I'll fill thebloody hole in.
The cynical old beggars I was referring to way back are the ones who for example, justify leaving compression joints under floors because they "know how to make "and theirs "don't leak".
-------
"so measured pressures are permitted to vary + or - 1 millibar. "
ummm, no comment!
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