HVAC Questions? Ask an HVAC Expert for Answers ASAP
When you mention the boiler manual, are you talking about the frost protection?
OK. I think we can ignore the DHW frost protection for now, unless your boiler or cylinder is outside the house.Has anyone worked on the installation recently, who might have adjusted the cylinder thermostat?Are you able to see the thermostat and any scale next to its setting knob?
I'm slightly unnerved by your last post - are you saying that an old part was fitted to the new boiler? I suspect you aren't, in which case are you saying that the old room thermostat was used? Or if neither of those, what old part was fitted and to what?
If the cylinder thermostat isn't being used then it's an act of incompetence on the part of the installing/maintaining engineer. Lets go with the idea that it's connected, but might be faulty. Can you either describe it, or post a photo of it?
Yes - we can continue in the morning.Please dispel all assumptions about what's working and what isn't. The only way to find the problem is to assume nothing and to test and diagnose. The water temperature is supposed to be controlled by the cylinder thermostat, so that's a prime suspect. It would be helpful if you can tell me what it's currently set to, without changing it, or post a photo of it.