Central Heating Repair

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Revision as of 17:56, 15 February 2007 by John Stumbles (talk | contribs) (cerate article)
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This article is about Central Heating systems using hot water as a heat-carrying medium. (Warm-air systems are sometimes found in the UK but their design and installation is not covered here. There is a discussion on updating existing warm-air systems here)

The article is about diagnosing and fixing a faulty central heating system.

There are separate articles about:

This article is a skeleton: the main points to be covered are listed but some or all still need to be expanded


  • No CH or DHW
  • No CH, DHW OK
    • conventional
    • combi
  • CH OK, no DHW
    • conventional
    • combi
  • DHW OK, some parts of CH not working
    • rad(s) compeletely cold
      • balancing
      • stuck TRV
      • completely full of air
    • rad(s) lukewarm
      • balancing
      • faulty TRV
    • rad(s) cold at top
      • bleeding
    • rad(s) cold at bottom
      • sludge

rads constantly need bleeding

  • air or hydrogen in system? (lighter test - with care!)
    • corrosion:
      • inhibitor?
      • vented system? - pumping over?
    • air
      • pinhole leaks?
      • vented system? - pumping over?