the problem i have with my baxi solo boiler is that it will only heat the water and heating together , when the programme button is pressed for heating only the boiler goes off could it be plumbing or electrical problem ?
If in the past you have been able to use your heating only then a motorised valve will be faulty,but my guess is that the boiler was updated but the system wasnt so you cant have heating only with your present set up.If i am right the system would need a fairly major revamp to give you what you want.
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