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Discuss unvented central heating problem?? in the Central Heating Forum area at

  1. Tom.davenport12

    Tom.davenport12 New Member

    Hi guys i have an unvented cylinder and system boiler in a coach house and have good hot water but the central heating is struggling to get hot, just staying lukewarm throughout even flows and return from the boiler when fired up. It seems the boiler tries firing but doesn't get anywhere so the keeps cutting out. any ideas would be brilliant please????
  2. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    check the port valve is working
    check the pump is pumping

    its normally something simple if hot waters working
  3. Tom.davenport12

    Tom.davenport12 New Member

    Ok thank you is there any sure way of checking the pump and port valve? the pump is running but doesnt sound too powerful. i do suspect the system itself as black water when bleeding rads. could it be blocked with sludge do you think?
  4. daWilko

    daWilko Member

    Hi - I'm not a plumber (just a 'umble spark) but I think it could be blocked flow, weak pump, stuck valve or even an electrical fault. Your local friendly Gas Safe Person could diagnose and fix for you.
  5. daWilko

    daWilko Member

    Re reading your original post - if your programmer allows it, turn off HW and see if any more heat gets to the rads. Just a thought on a cold night .
  6. Gazzzz101

    Gazzzz101 New Member

    Sounds like a circulation problem, check the pump, the port valves of if pressurised check the pressure.
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