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Discuss Circulating pump valve nuts in the Oil and Solid Fuel Forum area at

  1. Gazzt

    Gazzt Active Member

    does anyone have tips on getting seized circulating pump nuts off. It's especially annoying in tight boiler houses. All suggestions welcome :)
  2. rpm

    rpm Trusted Plumber Top Contributor!!

    Tap Tap with hammer lightly first?
    • Agree Agree x 2
  3. townfanjon

    townfanjon Trusted Plumber GSR Top Contributor!!

    Can be a nightmare. Loads of wd40 and a massive pair of grips . Otherwise I cut the pipework and put new valves in
    • Agree Agree x 1
  4. Harvest Fields

    Harvest Fields Trusted Plumber GSR Top Contributor!!

    I use an 18” pair of grips and a small lump hammer
  5. SimonG

    SimonG Trusted Plumber Top Contributor!!

    Chisel and hammer, tap them round. For really stubborn ones I hacksaw the ring off.
  6. Best

    Best Trusted Plumber Top Contributor!!

    Hit them with a claw hammer all around, but mainly on the strongest part of the nut, towards the valve body. (If you hit the side of nut near the pump too severely, it is weaker and risk of deforming the nut and it seizing worse). Some take a while to ease and need plenty of patience.
    On really awkward pumps I have slackened the valves on the copper pipes slightly to aid turning the pump around to get access to all sides of pump nut to hit with a hammer.
    If pump nuts are very badly rusted in, or in terrible condition, then just junior hacksaw the nuts and split them off with a flat blade screwdriver and hammer, after ensuring valves are fully closing off.
    Carry new pump nuts for the job and complete pump valves as sometimes better to just replace whole lot.
  7. heatservice

    heatservice Member

    Brass nuts can distort the more pressure you apply, I have sometimes been successfully when using my grips backwards, may sound stupid but try it, heat usually helps also.
  8. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    normally tighten them a wee bit first and then undo normally works if not undo the nuts and replace the valves as ive already drained down due to most not holding / dirty
    • Like Like x 1
  9. Gasmk1

    Gasmk1 GSR

    Hammer has always worked for me
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