Technical

I have A4 Golden Fleece, which had not run for a few years I managed to get to run ok for a few times but then a tripping problem started - audible alarm red light out on the controller, the transformer light remains on. as the boiler gets up to steam and runs, I assumed it would be the thermal cut-out. I have replaced the thermal cut-out and cleaned the wheels and connections. On the first steam up and running it's ok, but after letting the boiler cool down and then refilling and going through heating process it will run for ten mins and then trip - audible alarm red light out on the controller, the transformer light remains on, any further attempts will result in the controller trip. But wait 24 hours it will run fun for the first run. I am running the train on the rolling road.

Any advice / help would be most appreciated