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  1. Oakwood109

    Oakwood109 Member

    Hello all,

    I wonder if anyone can help me on the following issue I have with my central heating system

    I have a Worcester Greenstar 24rsi (installed 2013) powering 9 older rads on my 1930s semi. It’s an open vented cylinder system with a Honeywell programmer.

    I have had my bathroom done and in the process I had a towel radiator fitted to the system. Since then I have had only three rads warming up properly. The new rad was piped directly into the bedroom rad with 1.5 copper pipe and is red hot, as is the bedroom rad that the plumber plumbed the towel radiator to.

    The fill pipes to all the rads are too hot to touch but the majority of the rads don’t get hot at all. There is also an almost constant popping / banging noise across the system, particularly prominent when the system turns on but is also there when the system has been on for hours too.

    Have tried balancing but that hasn’t worked. The banging noise doesn’t seem to be the pipes hitting against tight floorboards, it is definitely coming from within the radiators.

    I do not have independent control of the hot water, both that and the heating need to be turned on for the system to work. I am getting that sorted and also a new cylinder stat as that wasn’t working either.

    Bit stuck on this so wondered if anyone had any advice?

    Thanks a lot in advance
  2. Chalked

    Chalked Plumber GSR

    You probably have a one pipe heating system. When extending to an extra radiator, the loop needs relocation and extending to the new rad.
    If this has not been done, it will never work. Generally, only plumbers over 40 would have experience of this.
  3. Oakwood109

    Oakwood109 Member

    OK thanks a lot for replying. My current plumber is a young lad so coukd explain it! Is it fixable or should I look at changing to a 2 pipe system? Thanks again
  4. king of pipes

    king of pipes Trusted Plumber GSR Top Contributor!!

    Sounds like you have a air lock in the system left from your recent towel rail install , turn off the rads that do get hot and all the others except one fire up the heating and vent the rad till hot open up one at a time venting each one in turn this should clear the air. Kop
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