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Discuss Radiator stopped working after boiler conversion in the Central Heating Forum area at

  1. shk

    shk New Member

    Hi, I am new to this forum and I need help with my central heating.

    I replaced my old boiler with an Intergas HRE 28/24 and it was running in conventional mode. The bathroom radiator was always hot as it was a bypass.

    Recently, I had the original installer convert the boiler to run in combi mode but then the bathroom radiator stayed cold all the time. It has 8mm pipes that run under the floor boards. Adjacent to the bathroom is the airing cupboard which used to hold the hot water tank. It now contains the expansion vessel (EV), an air release valve and the filler loop.

    The supply pipes runs up and then down into the floor. The first branch off from the supply pipe is to the EV and also to the return pipe. The second branch off is to the air release valve and also the filler loop.

    The radiator had been replaced with a new towel radiator and was connected directly to the supply and return pipes with 15 mm pipes. The radiator was still cold. Finally it was connected to only the supply pipe - still the same result as before.

    I suspect the problem may lie with the EV connection but I am no expert and the installer has no idea what else to do. Any advice will be most welcome. Thanks for reading this.
  2. snowhead

    snowhead Well-Known Member

    Pictures of the Airing cupboard layout would help.
  3. king of pipes

    king of pipes Trusted Plumber GSR

    I would say the 8mm pipe is the problem it is eithier air locked or blocked , isolate the valves drain out the water in the rad connect a hose to one of the valves turn on the valve put the hose into a drain turn on the valve and then the filling loop and blast out with water until it runs clear, isolate the rad valve and filling loop move the hose to the other rad valve and repeat the process then refit the rad fill and vent the system should hopefully work cheers kop
  4. shk

    shk New Member

    Hi Kop & Snowhead,
    Thanks you for your interest. With regard to the radiator, it has been replaced by a a new towel rad and the old pipes have been capped.
    Please look at the 3 pictures for the pipe arrangement.
    Bottom pic.- the 1st pipe on the right side is the supply pipe going down under the floor; next to it is the return pipe and next to that is the supply pipe coming up from the floor and joined to the 1st pipe via T joints. The radiator pipes exit from the wall ( far left and behind the return pipe) and join the supply pipe at its tip and below the t-piece. The 1st branch off on the supply pipe is to the expansion vessel (the joint is hidden by the return pipe, but this pipe is next to the supply pipe and the mains pipe (see mid picture)).
    The 2nd branch off is to the filler loop and air valve (mid picture).
    Mid picture: the pipe to the expansion vessel is joined to the return pipe.
    Top pic: the expansion vessel is connected to the 1st pipe branching off the supply pipe.
    I hope I have provided sufficient info for you to make a judgement.
    pipes bottom1.jpg pipes mid1.jpg piipes top1.jpg
  5. king of pipes

    king of pipes Trusted Plumber GSR

    Sorry to say but that is a very poor upgrade the radiator will not operate satisfactory piped up like that. regards kop
  6. SimonG

    SimonG Trusted Plumber

    Rad piped off of cylinder circs. Cylinder now gone so needs piping to heatin f and r?
    • Agree Agree x 1
  7. shk

    shk New Member

    The radiator was left untouched when the cylinder was taken out and it then stopped working. When the new one was put in, it was connected directly to the supply and return pipes in the cupboard and that did not work either.
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