PCB Schematics

Discussion in 'General Electronics Chat' started by roadey_carl, Feb 12, 2012.

  1. roadey_carl

    Thread Starter Active Member

    Jun 5, 2009
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    Hey,

    I've been trying to repair a boiler PCB without much luck. Does anybody know if theres a way I would be able to get a schematic for somewhere? maybe theres a website that has a loads on, or is it something the manufacture wont release?

    its a potterton suprima 60 PCB.

    I've looked everywhere so though I might ask anyone on here where they find the schematics for the PCBs' they repair?

    Thanks,

    Carl
     
  2. praondevou

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    Jul 9, 2011
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  3. roadey_carl

    Thread Starter Active Member

    Jun 5, 2009
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    I've got the manual fault codes etc.....
    I know the PCB is faulty but everyone just says change it.... I'd like to fix it!

    Its a two layer board. I can kind of understand how it works up to a certain extent, but I'm stuck at the moment so a manufacture schematic would be really helpful. I've emailed them but have had no response :(

    I'll post a picture later, and explain what it does to see if anyone has any ideas!
     
  4. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Show the boiler and it's relevant data...and may be I can help u
     
  5. SgtWookie

    Expert

    Jul 17, 2007
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    You may find this helpful:
    http://www.fogma.co.uk/electronics/329.html
    That chap was determined to fix his as well.

    This search:
    http://search.diynot.com/forum_sear...tbytime=0&author=&search=Search+Forum&stype=0 e
    will find lots of other Suprima 60 owners that are/were having problems (many related to lock-out).

    Read the caution at the top of this page (at least that much):
    http://www.cambourne.info/boilerparts.html
    If you read further, you will see numerous people found many dry (poor) solder joints on the PCB; in quite a few cases, simply re-soldering the connections on the PCB will fix the problem. If you call the manufacturer, they will deny that there have been any reported problems with the Suprima PCB (you're the first!) even though BBC's Watchdog program aired a segment on the Suprima's boiler problems in February of 2007. Apparently, they redesigned their PCBs around that time, and replaced the PCBs in any new units that hadn't shipped. If your unit was made/installed prior to perhaps March of 2007, yours may have the newer PCB.
     
    Last edited: Feb 13, 2012
  6. roadey_carl

    Thread Starter Active Member

    Jun 5, 2009
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    Very interesting...this boiler is a newer PCB but they still have problems ( as you can see from the 3rd link Sgtwookie posted) It seems somebody may have designed a rather poor PCB!! I must admit the build quality seems to be pretty good, I still think a transformer is much better then using a capacitate power supply, they seem to be causing problems everywhere these days. Anyway, I made a video of what the PCB does, its only a few minutes long.

    http://www.youtube.com/watch?v=giLbuP22xiI&feature=youtube_gdata

    Also here are some pictures of it:
    http://imageshack.us/photo/my-images/837/001xid.jpg/

    and heres a scanned copy of the fault codes and wiring diagram :

    http://imageshack.us/photo/my-images/825/wiringdiagramk.jpg/
    http://imageshack.us/photo/my-images/833/faultcodee.jpg/
     
    Last edited: Feb 13, 2012
  7. roadey_carl

    Thread Starter Active Member

    Jun 5, 2009
    116
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    Any Ideas anyone?
     
  8. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Gimme some time to read everything

    {ed}

    What is it's current status and fault ur getting ?
     
    Last edited: Feb 14, 2012
  9. SgtWookie

    Expert

    Jul 17, 2007
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    Carl,
    You appear to be powering up the board when it's sitting in it's box with no stand-offs or screws to ensure that it is in it's proper place; and the box has several high spots that are supposed to contact areas of the board (for support) that are not populated with components or traces. But, since you don't have anything locating the board in its' proper place, you may be shorting some components/circuits to the box.

    It seems that the lock-out occurs several seconds after the board has attempted to light the burner. That makes me think that the temp sensors' value is out of range, the wire to the board is broken, or the circuit on the board that monitors the temp sensor is faulty.

    I don't know what your temp sensor actually is. In the last few places I've been in that used gas for heat, the temp sensor was a thermocouple, not a thermistor. But, I have no idea what they might've used.
     
  10. roadey_carl

    Thread Starter Active Member

    Jun 5, 2009
    116
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    R!f@@, the current state is calling for heat for about 10secs. The the light will flash red... If I switch the air pressure switch, it will go back into firing up the igniter.

    SgtWookie, I cant screw it down as the stand off's are on the top of the enclosure... IE I wont be able to access any of the circuit. It is however sat in the bottom plastic part of the enclosure so nothing can short out!
    What you said about the temperature circuit being fault is what Im thinking also, I'll disconnect the pot from the circuit and try again if it does the same thing we'll know its something to do with the signal from the POT and from the thermistor... I know the thermistor works as I've tested it and it vary's anything round 1MΩ to 0. bit like you said, it could be the wire so I'll do a continuity test!
     
  11. roadey_carl

    Thread Starter Active Member

    Jun 5, 2009
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    I just disconnected the pot... it made no difference! I traces the connections back to a LM224DG, theres 32.8V +/- I dont really know how to test further than this... any advise?
     
    Last edited: Feb 15, 2012
  12. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Hang on....! I need some time to think about this.
     
  13. roadey_carl

    Thread Starter Active Member

    Jun 5, 2009
    116
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    its a tricky one.... I infact measured 32.8vdc not 24 as I said before!
     
  14. BSomer

    Member

    Dec 28, 2011
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    What exactly is the "spark/flame detection electrode"? Does it actually look for a flame in the IR or UV spectrum? If that is the case, your detector or the circuitry for it amy have gone bad.
     
  15. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Is the LED giving a flash or continues lit

    If it is the later case, then I will need better high res close up of the complete PCB. So I can study it.

    Both sides with good lighting and no flash glare.

    Without looking at it I cannot say anything since the Manual has no schematics.
     
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