The central heating will only work when the hot water is on, and we can't heat the water without radiators getting warm.
If only the heating is turned on at the controller nothing happens regardless of room stats etc.
If the hot water is turned on at the controller both heating and hot water kick in, if the cylinder stat is then turned down everything goes off, again the room stat has no effect.
The 3 way valve does not appear to function but not sure if it is faulty or incorrectly wired or maybe the controller. The 3 way is not wired to the central heating off in the controller but not sure if this is the cause.
Suspect the system has never been right since I moved in but didn't notice in winter as both were working together.
it is a pumped system with a Myson Orion boiler, Drayton tempus three controllerand a Siemens - landis & staefa MA-V322C three way valve
Any help would be most welcome