Did you try what Ian said when there was a demand for heat?
They do sometimes free and start spinning again.
There is an isolator valve either side of the pump. Turn them off undo the connections pump side, slide old pump out. If you get same pump should...
If it's not spinning then then new pump time
Are you sure the pump is actually pumping?
Sounds as if the pump is not getting heat away from the heat exchanger quickly enough.
Have you tried...
Yes would say this is fine to gas regs.
Only thing I would mention, I remember there being a safety bulletin a while ago regarding the 'relaxing'...
Ok best of luck with it
Is the flow rate on the hot water ok?
Does the burner actually light when opening a hot tap?
What happens if you leave the tap...
Not sure whether you are indicating one of the pipes leaking or the big red expansion vessel.
Did you re-pressure when cold to 1 bar?
If the boiler doesn't react when you turn the hot tap on then I would start with the flow sensor.
Judging by the shoddy work you have had done on...
When you turn a hot tap on does the boiler do anything at all?
Does boiler work ok for heating?
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