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    Radiators turning on when hot water used


    Why do my radioators turn on when the hot water tap is turned on? We've turned the dial on the boiler to "water only" but it hasn't worked. We have an ideal combi boiler. Is this something we could fix ourselves or would we have to get a plumber in? If so, how much would this cost? Thanks. Much appreciated for any advise.

    Asked by Zaheera on 17th May 2022
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    Best Answer

    Hart of heating

    "Hi there, it sounds to me like the diverter valve is faulty but you will need to get someone out just to carry out tests and confirm, unfortunately you will need a engineer to carry it out and depending on the company is will probably cost between 130-300."

    Answered on 18th May 2022 - Member since Apr 2022 - report
    Djendel and son plumbing

    "The boiler diverter stuck on the mid position, need replacing"

    Answered on 18th May 2022 - Member since May 2020 - report
    FerGas Services Ltd

    "This is the divertor valve in the boiler…. You need a gas safe plumber."

    Answered on 18th May 2022 - Member since Nov 2021 - report
    Mr Reactive

    "You would need an engineer. Most likely the diverter needs changing or the plate to plate is clogged up. Give us a call on Bradford 752 852 for free phone advice.

    Mr Reactive"

    Answered on 18th May 2022 - Member since Jan 2022 - report
    HJ Plumbing LTD

    "Hi Zaheera, it seems like your diverter valve is faulty and will need replacing. You will need an engineer to replace this.

    What is a diverter valve?
    A diverter valve is a mechanism in a combi boiler that opens or closes to direct hot water either to radiators or taps and showers. Diverter valves are not found in system or conventional boilers because the valve is only needed in boilers where water is heated on demand, whereas system and conventional boilers store hot water in a storage cylinder.

    If a specific hot water tap is turned on, the combi boiler will heat water and the valve will direct the hot water to the tap rather than to the home’s radiators or other taps. If the heating is turned on, the combi boiler will do the same for the radiators. If the heating is on and someone turns on the hot tap in the shower, the diverter valve will prioritise sending hot water to the shower instead of the radiators until the shower is turned off.

    Hope this helps.

    Kind Regards,
    HJ Plumbing LTD"

    Answered on 18th May 2022 - Member since May 2022 - report
    Snc plumbers

    "The "changeover valve" is worn."

    Answered on 18th Jun 2022 - Member since Jun 2022 - report

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