Which is why I suggested that the voltage could be dropping off when the heater is connected due to poor connection upstream of the element or it could be poor connection between the cap and the element itself.
Just to update those who maybe interested and thanks for all the useful input.
After eventually finding out that it was indeed a Nobo heater the part that was faulty, well parts actually were the regulator now fitted and working and the program control clock is faulty too, but if the control is removed from the circuit a manual operation can be used.
What pyssed me off was that the Nobo wall heaters seem to be exclusive to Creda Heating which TBTH their customer services were appalling. I left message after message with them and after the 15th go was informed that they didn't deal with the spare parts, even though they have a contact details on their website that clearly says "Spare Parts" anyway managed to find out who does deal with the spares now.
Thanks again for all those who offered help!
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