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Discuss Boiler trips the fuse in the Plumbing Forum area at

  1. Inverness

    Inverness Plumber GSR

    ive had a friend who's boiler is tripping at the fuse board when they turn on the boiler. It is a seal system but it has dropped too zero? I think the pump has stopped work or something and the boiler has over heated and activated the high limit stat too. Why would a boiler pump fail?
    It's a old stelrad group ideal boiler. I replaced a new zone valve about 3 months ago. Can someone explain why this would happen or is it wear and tear. Great and appreciate your thoughts and experience very much so. It's Friday tomorrow! Have a pint on me...
  2. townfanjon

    townfanjon Trusted Plumber GSR

    Disconnect the pump , does it blow the fuse then ?
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  3. Inverness

    Inverness Plumber GSR

    I'll be going round tomorrow with a new pump just in case cheers
  4. Best

    Best Trusted Plumber

    Circulating pump fails if sealed system is allowed to run at zero pressure.
    Have seen this happen often on oil boilers that normally have no pressure cut off switch.
    I assume the pump can't pump water if no system pressure and pump motor windings overheat and get damaged. They usually have electric burn smell.
  5. Murdoch

    Murdoch Member

    Tripping what on the fuseboard?

  6. heliotrope

    heliotrope Plumber GSR

    If a problem like this is so difficult then you should get an experienced plumber in to explain it for you.
  7. heliotrope

    heliotrope Plumber GSR

    If a problem like this is so difficult then you should get an experienced plumber in to explain it for you.
  8. Inverness

    Inverness Plumber GSR

    All I was told boiler trip at the fuse board. It's an old style fuse board.
  9. Murdoch

    Murdoch Member

    Hum . not really enough to go on really but if its an older style that would suggest no RCD's and therefore the fault is a dead short .. not good.
    Last edited: Apr 27, 2018
  10. Last Plumber

    Last Plumber Plumber GSR

    Don't take this the wrong way inverness. It's not intended as an insult or anything like that.

    If you don't feel confident at fault finding on the electrical side of things, I would recommend you get yourself some qualifications and experience on it. Best thing is to work with a Heating Engineer or Spark, Or both would be great.

    It is not worth trying to use guess work.

    There are ways/methods of testing on anything electrical. You should be able to find the fault with 'most' things electrical on Heating with a good quality Meter like the Fluke 116.

    If the 'fuse' is blowing or Mcb tripping, it is due to an overload of current, probably a short circuit of some kind.

    If you are going to attempt it yourself, make sure it is electrically isolated before you start taking the cover off. You don't know what lurks beyond!!!
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  11. Inverness

    Inverness Plumber GSR

    I'm still an apprentice just passed my oil ticket today I've already got my gas. So I do learn a lot from you guys and I don't do enough electrical testing in fact there's not a lot of plumbers that do this kinda work and the ones that do are lucky to do so. I'm going round to that job tonight. I'm going to test the pump if there's power going to it. Cheers
  12. Last Plumber

    Last Plumber Plumber GSR

    Ah, I see. Well we were all there once!
    You might find that you can't test if there's power to it due to the Fuse/mcb problem!.
    Just a thought.
    Have you got a meter?

    Well done on the Oil!
    • Like Like x 1
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