Had a chat with my local dealer and they gave me a spare ignitor/ glow plug, replace the igniter in the pot and put it all back together. Followed the startup procedure, ignited fine. I let it burn for 10 minutes then hit the off button and let it go through its cool down process. I thought all was good.
Mains still plugged in but switch in off position and power button pressed so no screen display. about 30 minutes later i could smell smoke.
so with power off and switch off the ignitor was still going strong.
unplugged it from the mains and waited for it to cool off at which point i could see down the feed tube a nice glowing red were the pellet were still burning inside the arbor tube and smoke working its way out of the hopper.
Unwired the ignitor, turned the unit back on and pressed prime to try and push the smoldering pellet into the pot.
Didn't considered the fans would also kick in and feed oxygen onto the smoldering pellets which just made it worse.
resorted to getting the hose pipe out to put everything out, closed the lid , made a cuppa tea.
Think ill be calling the dealer tomorrow.