OP here. First apologies for not being clear on my post. By this point, I should know better. Thanks for the responses.
The problem is solved, and as in many cases it was user induced, even with the best of intentions.
During my routine and preventative maintenance procedures, I separate electrical connections, ensure that they are clean, add a tiny bit of di-electric grease and reinstall with a tight connection. Except this time.
I'm not sure whether it was the ECO or thermostat connection but on one of them, the connector went into the protective cover but did not connect.
Knowing that it had to be a common thread, I disconnected them, made sure they went back on securely and it fired right up. Lesson learned.
Creative, thanks to a previous post of yours, the thermal cutoff was the very first thing I checked.
Thanks again for the tips.