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Discuss Wire up a external oil system boiler in the Oil and Solid Fuel Forum area at UKPlumbersForums.co.uk.

  1. Inverness

    Inverness Plumber GSR

    hi guys, my sparky has let me down.

    I need to wire up a external grants system boiler.
    I've got in place 4 core inside the boiler.
    In the house there's is a existing programmer with a fused spur for a pump which now isn't in use anymore and a fused spur for the old boiler. There was a utility boiler with a external pump on the system which isn't required anymore.

    I know we need a live permanent for the frost stat and switch live.

    Any ideas how I can wire it up with your help?
  2. Brambles

    Brambles Active Member

    Please don’t take this as a negative comment.

    Wait for the electrician to be available or source a new electrician.

    It is very easy to “blow” the pcb on a Grant boiler - that equates (in cost terms) to about 4 days for an electrician in Oxfordshire.

    Be patient and get the right skills around you.

    Apologies if this is not what you want to hear, but in my experience of Grant boilers, the pcb fries before the fuse blows!!
    • Like Like x 1
  3. Inverness

    Inverness Plumber GSR

  4. Brambles

    Brambles Active Member

    If you are really stuck contact me on [email protected] and I can talk you through it - but you would be far better with your Sparkie
  5. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Perm live
    Perm neutral
    Perm earth

    Then your switch live

    No need for a pump live as I believe it’s internal to the boiler

    As for frost pipe stat? Frost stat or both ?

    Normally just wire them perm live and out going to pump / switch depending on what you want
  6. Millsy 82

    Millsy 82 Plumber GSR Top Contributor!!

    Are you saying the cost of a pcb is the same as 4 days for an electrician. I'd love to get an electrician for less than £25 a day if that's the case. :D
  7. Brambles

    Brambles Active Member

    Ha ha, I appear to have typed days rather than hours!!
    • Like Like x 1
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