rayburn 480k

Hello
We have a mark 1 rayburn 480k fitted with retrofit ecoflam burners.
Cooker works perfectly.
Heating side goes through the starting sequence , fires then cuts out after 5 seconds. It sometimes fires and runs for a few sequences, then locks out again.
We discovered that if we didn't push the magic eye all the way in, about 4mm short, it solved the problem, but now even that doesn't work.
We have change the magic eye , swapped with the cooker side, but no joy.
My husband is becoming quite demented and I am in no doubt that if the rayburn had been of a weight to lift, it would have been thrown through the window by now.
Contemplating buying a used alpha or stanley cooker if the problem persists.
We had the rayburn serviced, but they left us with doubt as to their abilities, as we discovered that they had fitted the wrong size nozzles!
Any suggestions?
Fiona

 

The joys of where we live.
Only local ones were the ones we used.
Thanks anyway.