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Discuss Sooted up boiler and other tips in the Oil and Solid Fuel Forum area at

  1. WHPES

    WHPES Trusted Plumber GSR

    Just a reminder to folks that when you come across a sooted up boiler (usually where a conventional flue is blocked, a balanced flue gasket breaks down (ex the early Trianco square balanced flues) or a pump wears out), after you have de-sooted the boiler and fixed the problem, it will take several hours for the loose soot to burn off and give you a reliable CO reading on your analyser.

    Use your smoke pump to get the smoke down, leave the boiler running and come back in a couple of hours to set up with the analyser.
    • Like Like x 8
    Last edited: Jan 28, 2013
  2. Bunker

    Bunker Plumber

    I'd add to that, leave the boiler running over aired or lower jetted for a few days if bad. Smoke tests early will show yellow which is your unburnt soot.
    • Like Like x 4
  3. Dotty

    Dotty Guest

    Great tips! Thank you. Any other tips or tricks please add to this thread

    Gonna sticky this one.
    Last edited by a moderator: Jan 30, 2013
  4. kimbo

    kimbo Guest

    Better still chuck in a soot stick or spray with dualx to get rid of it all
  5. Bunker

    Bunker Plumber

    Top tip:

    Black nozzles/ stems often mean late ignition. This doesnt mean the electrodes come on late, it means the oil actually 'catches fire' after alot of oil has already been sprayed in. This causes a whump on start up which, as well as being noisy, blows oil back down the blast tube.

    The best way to check is to take the burner out, remove the coil or the coil connector, and fire it up. A bit frightening at first but with the coil off it wont actually fire (although handle it as if it will, just to be safe). You can then watch the ignition arc and where the air takes it - it should be pushed by the air beyond the nozzle and into where the oil spray should be.

    This can be caused by a few things including:

    1. electrodes too close together so not much of an arc - bend apart, being careful if ceramic insulation.
    2. electrodes too far back or forward - adjust to suit
    3. electrodes too close to blast tube or nozzle and the arc not then being blown into the atomised oil - adjust to suit

    The above is not comprehensive so please feel to add to it.
    • Like Like x 2
  6. WHPES

    WHPES Trusted Plumber GSR

    Sooting up can be caused by several problems if it just happens suddenly.

    Blocked flue (birds nest etc)

    Debris on baffles if not serviced for some time

    Blocked air intake or fan (leaves, cat fur, dead mouse etc)

    Faulty nozzle
    oil leaking from behind nozzle (a few turns of PTFE round the nozzle thread will cure this)

    contaminated fuel

    Failed flue seal between the inlet and flue on a balanced flue. Common fault on the early Eurostars. See here:

    The part number for these gaskets is Trianco 221647 and you need 2 of them and a bit of silicone grease for assembly.

    Some of the early eurostars don't have the red gasket in which case remove the flue sections and reassemble with high temperature silcone
    Last edited: Feb 4, 2013
  7. Bunker

    Bunker Plumber

    or sticking a wrong nozzle in - I did that recently, lord knows how I picked up the wrong one - .85 instead of a .75...this is the result over 3 days:

    Attached Files:

  8. Roger Welton

    Roger Welton Plumber GSR

    Sooted up boiler and other Trick.

    The nozzle seals on the flat face of the nozzle assembly to the rear of the nozzle, not the threaded section, sometimes get a bit of dirt in the wrong place causing them to drip, if eroded then a replacement nozzle assembly is required.
  9. WHPES

    WHPES Trusted Plumber GSR

    If the nozzle assembly mating surfaces get slightly marked or deformed you can get a leak. A lot of the problems tend to be on old and obsolete burners where the nozzle has been taken out many times and as such spare parts are often unavailable.
  10. Bunker

    Bunker Plumber

    Perhaps we should have a section where, when taking out an old boiler, we can announce it and if anyone has a problematic version, they can ask for parts from it.
    • Like Like x 2
  11. Roger Welton

    Roger Welton Plumber GSR

    My garage does look like a burner graveyard at times, tend to keep a couple of old burners around for emergency use.
  12. SimonG

    SimonG Trusted Plumber

    I always have a standby ready to go.
  13. WHPES

    WHPES Trusted Plumber GSR

    I always save burners and have loads on my racking in various stages of dismantlement where I have raided for bits. I've got 2 RDB burners ready to go.

    I've got loads of baffles for obsolete boilers so if anyone needs anything drop me a line.
    • Like Like x 2
    Last edited: Feb 5, 2013
  14. SimonG

    SimonG Trusted Plumber

    I find rdb's are a bit like rocking horse poop as far as a standby burner. I've broken all my burners down bar a b9 and I'm down to my last BH011.
  15. Best

    Best Trusted Plumber Top Contributor!!

    I have so many BHO 11s, I have no idea what amount are lying about.
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