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Discuss CH P.D.Valve always extended - Constant CH from Potterton Performa 24 Combi in the Central Heating Forum area at

  1. Jack of All

    Jack of All New Member

    Hi all, I see this question has been asked before but I haven't found a full answer yet, so hoping someone can help.
    I have a Potterton Performa 24 combi boiler which provides CH even when the dial is in the 'CHW only' position.
    Following several other threads advice the entire manifold and differential valves assembly has been replaced and also the CH microswitch but the problem persists.
    What I have noticed is the CH Pressure Differential Valve pin is always activated/extended once the dial is turned on, so pushing the microswitch. Is this the normal position for the pin? Is this pin just confirming there is adequate pressure to the PCB?
    Im now thinking if everything is firing and valves working as they should then it must be a PCB problem.
    Any thoughts or advice will be much appreciated.
    I will be getting a professional to fix, I just wanted to figure it out the issue first.
  2. AMGasServices

    AMGasServices GSR

    Do you have any external controls ? May be they’re calling for heat.

    Tbh, you shouldn’t have opened the boiler. You’re putting yourself and your family at risk.

    Please post in the find a plumber etc... section with your location someone local will be able to assist you. Please see link below.

    Looking for a Heating Engineer? Post Jobs Here
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