Paul Barker said:
Why would a PME carry a hell of a lot of current?
Surely you mean similar AC potential
Fuses blowing in pcb's
- Thread starter newcomers
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Why would a PME carry a hell of a lot of current?
Surely you mean similar AC potential
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I once went to a boiler which had stopped working after two years.
It turned out her father was an electrician and had found her flat was reverse polarised and corrected it only to leave the boiler unexpectedly not working. What a coincidence!
The Polish installer finding the house reverse polarised presumably just reversed the boiler?
OR
The Polish installer had wired the boiler reversed and it worked perfectly?
We will never know but it was a very easy repair for me!
Tony
It turned out her father was an electrician and had found her flat was reverse polarised and corrected it only to leave the boiler unexpectedly not working. What a coincidence!
The Polish installer finding the house reverse polarised presumably just reversed the boiler?
OR
The Polish installer had wired the boiler reversed and it worked perfectly?
We will never know but it was a very easy repair for me!
Tony
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newcomers said:
yerah, but the problem is that, from your posts , you don't seem to be competent
like the other day you couldn't differentiate between a pcb or a gas valve problem
you really shouldn't, by law, be working on gas appliances
you are not competent
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corgiman said:
But there are two potentially contradictory requirements here
1) having passed the ACS / being CORGI regd and
2) being competent
As you well know, I'm on a crusade against the incompetent CORGIs
I have no issue with those who know what they are dong
tindependent of any other legislationhe law says that you must be competent. Whether you are CORGI reg'd or not, IMO, this still applies
raden said:
Corgi is about working safely and being able to spot unsafe situations and check basic requirments on gas appliances.............NOT about being able to check resisitances across a solenoid.
Come on lads fair is fair
How the heck can someone learn how to do the job without actually doing the job, not even the apprenticship was 100% comprehensive let alone the frankly rubbish training all these poor sods are getting now!
All training does is give you the confidence to try and the knowledge of where to look if you dont know how to do soemthing.
I have been in the trade twenty odd years and every single day I am faced with something I have never seen before but I believe I am fairly competant.
Unlike thelucky boys who work of the makers the rest of us face alsorts of different boilers everyday and IMO there is no way we can be experts on all of them?
I have a lot of re4spect for chaps like "newcomer" who have the cajones to acutally come on here and risk ridicule by asking how to do it, better that then they keep sctum and xcock it right up aint it?
Any way I may be wrong I often am but I say let us old sods help the young eager beavors
How the heck can someone learn how to do the job without actually doing the job, not even the apprenticship was 100% comprehensive let alone the frankly rubbish training all these poor sods are getting now!
All training does is give you the confidence to try and the knowledge of where to look if you dont know how to do soemthing.
I have been in the trade twenty odd years and every single day I am faced with something I have never seen before but I believe I am fairly competant.
Unlike thelucky boys who work of the makers the rest of us face alsorts of different boilers everyday and IMO there is no way we can be experts on all of them?
I have a lot of re4spect for chaps like "newcomer" who have the cajones to acutally come on here and risk ridicule by asking how to do it, better that then they keep sctum and xcock it right up aint it?
Any way I may be wrong I often am but I say let us old sods help the young eager beavors
raden said:
Thats funny because if I remeber correctly, most people were saying it was the gas valve, but I went for the pcb and it worked
+++++++++++++++++++++++++++++++++++++++++++
oh and corgiman, youre a top man, I wish the rest of them on here were like you, willing to give us newbies to the game a chance.
The company I work for have some fairly big contracts, so im sure if they thought I wasnt good enough, or was a liabilty, they would stop me from working on my own.
Like somebody else has said, being competant is about knowing whats safe and what isnt, and working safley, not about knowing everything about everything
Newcomers no one is expecting you to know everything but you ask very basic questions. I remember talking to you about diaphragms a while ago.
These are all things you should know because before going out fault finding on peoples boilers you could have easily done a few boiler courses which will cover these basics.
I too got thrown in at the deep end but having the basic knowledge made it alot easier. Good luck mate
These are all things you should know because before going out fault finding on peoples boilers you could have easily done a few boiler courses which will cover these basics.
I too got thrown in at the deep end but having the basic knowledge made it alot easier. Good luck mate
The first issue to get your head around is whether the PCB carries mains voltage and actually provides power to other 'big hitters' in the boiler (ie. fan and PCB). Most do, through relays on the board. If so, and an on-board fuse has blown, you're very lucky! There are boiler around that are so badly designed that a faulty fan / pump can Muller the PCB as well!!
Another issue is 'live and neutral switching'. There are PCBs around which have TWO relays or external switches affecting the SAME component (eg. the fan). So with certain faults or even normal conditions on the PCB, it's possible to have mains on BOTH terminals of the fan and no movement although the fan is perfectly OK - the switch on the neutral side is open. Ghastly, potentially dangerous design but it DOES exist.
The first step with a blowing fuse is to disconnect fan, pump and gas valve from the board, and reconnect in stages, with suitable safety precautions.
Generally, component-level diagnosis on a PCB is not going to be cost-effective. If you repair it with generic components, you may be putting the boiler into an 'illegal' condition because its parts are no longer 'manufacturer supplied'. (This is debatable - cue Raden - but should be considered.)
Another issue is 'live and neutral switching'. There are PCBs around which have TWO relays or external switches affecting the SAME component (eg. the fan). So with certain faults or even normal conditions on the PCB, it's possible to have mains on BOTH terminals of the fan and no movement although the fan is perfectly OK - the switch on the neutral side is open. Ghastly, potentially dangerous design but it DOES exist.
The first step with a blowing fuse is to disconnect fan, pump and gas valve from the board, and reconnect in stages, with suitable safety precautions.
Generally, component-level diagnosis on a PCB is not going to be cost-effective. If you repair it with generic components, you may be putting the boiler into an 'illegal' condition because its parts are no longer 'manufacturer supplied'. (This is debatable - cue Raden
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more important is replacing defective components like for like
otherwise you are modifying, not repairing the pcb.
Certainly, anyone wgo repairs a boiler PCB should be competent at electronics. For example, if a 22 microfarad capcitor has gone, you can't just replace it with a 22uF capacitor, you should use the same working voltage (too low and it will blow, too high and you run the risk of it not working efficiently at the voltage used), working temperature etc
I don't think that "manufacturer supplied" is really relevant
otherwise you are modifying, not repairing the pcb.
Certainly, anyone wgo repairs a boiler PCB should be competent at electronics. For example, if a 22 microfarad capcitor has gone, you can't just replace it with a 22uF capacitor, you should use the same working voltage (too low and it will blow, too high and you run the risk of it not working efficiently at the voltage used), working temperature etc
I don't think that "manufacturer supplied" is really relevant
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newcomers said:
No, being competent (in this sense) means being able to work safely AND knowing what you are doing
In my opinion, for someone who is working in a professional capacity, this would include (in this case) being able to think to test the voltage to the solenoid ti identify whether the problem was with the pcb or gas valve
raden said:
and if you read the post youre referring too, you will see that I did that. You would have also have read that with the leads unplugged from the solonoid, the voltage on the leads stayed at 240V. You would have also read that when the leads were put back onto the solonoid, the voltage kept jumping from 0v to 240v..................you do remeber that dont you????
rob884 on newcomers pcb/gasvalve said:
ahem
PS i had a similar fault myself on a different boiler took a bit of a guess (can never be 100%) that it was the PCB even though a new one had been fitted. It worked but still searched here after to see anything similar and Raden had actually answered an almost identical fault and identified it as a faulty capacitor. Always remeber that whenever i see the boiler in question!
Just thought id share!
Newcs you just have to get an idea what values should be. Learn Ohm's law (amps x ohms = volts) and (power = amps x volts), realise that coils like in motors, solenoids etc have more resistance to AC than you measure with your meter. SOmetimes you'll see things quoted, eg :
In a Biasi service manual.
If you have specific Q's do come back.
In a Biasi service manual.
If you have specific Q's do come back.
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