Plumbing

Unvented cylinder problem

Anonymous user 28/02/2024 - 3.43 PM

I had a completely new heating system installed in Jan 2017. I have a Vaillant Ecotec 624 system boiler with a 250L unvented indirect horizontal cylinder in my loft. The cylinder (RM) was replaced Sept 2018 as it was leaking. I have noticed recently that the boiler is on almost constantly, as if the cylinder doesn't know when to stop calling for heat. My heating is switched off, but the radiators in part of the house are very hot. This was preceded by a spell of having insufficient hot water at times. i am struggling to get hold of the original installer and wondered if anyone had any ideas about what is causing this problem. I'm worried that this is potentially dangerous as the unvented cylinder does not seem to recognise when it has reached temperature.