Have problem with boiler or programer ? had Siemans rwb2e fitted but small metal bit inside fell off. fitted new Danfoss cp715 si straight swop . but boiler is acting the same as when old rwb2e was fitted .When it is switch on a small noise comes from inside , but it does not fire up ? do you think it is the boiler(.glow.worm 24hxi condensing boiler. or programmer ? gas man is coming later in the week. ps just had new gas cooker fitted but gasman could not check boiler after fitting as programmer was not working so he is coming back .