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Does a new boiler installation require all new pipes?

Leroy150 Member Posts: 1
We are upgrading our heating system in a 1960s 5 bed house from a gravity fed system to a pressurised cylinder system. We have received different advice regarding the need to replace all the pipes with one heating engineer saying we do (in case the current pipes can't accommodate the new system) and another saying we don't (saying the new system will challenge the existing pipe work but the current system has a level of pressure on it suggestive of easily being able to handle a sealed / pressurised system perfectly adequately).

I'm thoroughly confused and wonder whether anyone on here has any thoughts?



  • clammy
    clammy Member Posts: 2,668
    There’s a lot to converting a gravity system to a pumped system. The contractor should have experience in doing such conversions and be well versed in primary secondary pumping and return water temps to prevent condensation if install a conventional cast iron boiler. First n foremost a heat lose should be done and a edr evaluation of your existing radiators or convectors. Also they should not forget to properly clean your piping and at a minimum install y strainer or a dirt separator. Aside from this I would want to make they know what there doin and not some bs money grabbers there’s more to a proper install then pipes in pipes out and yes on there’s usually a decent amount of piping but a lot depends on what there working with. peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • Gordy
    Gordy Member Posts: 9,514
    What are the current heat emitters cast iron radiators?

    Really the best way to convert is home run the rads to manifolds.

    Hard to say what condition the present system is in. Some pics would be helpful of the boiler, and boiler piping, and some of the emitters.

    Agree with @clammy. Converting gravity systems to pumped can be tricky.

    There are plenty of gravity systems far older where piping is still used. If this was from the 60’s I question if it is even a true gravity system. Or the circa of the system.
  • delta T
    delta T Member Posts: 860
    What do you mean by 'Pressurized Cylinder' system?
  • Zman
    Zman Member Posts: 6,983
    Why not post some pictures of your system and bit more info on what modifications you are considering.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein