This boiler has an intermittent fault whereby hot water demand causes it to light and increase temperature as you'd expect. Then it will either modulate the flame down and keep the burner alight, or it will reach temperature and then the burner will go out with no modulation down and relight again in a few seconds.
I do understand the nature of intermittent faults but hope that some of you experts may be able to enlighten me.
I do understand the nature of intermittent faults but hope that some of you experts may be able to enlighten me.