Hi
Important point ---
May I enquire what kind of thermometer device are you using to check the oh so vital surface temps in the warm side ( and the cool end) ?!
As regards heating a RUB using a ceramic bulb , I only use vivs so I am not qualified to advise on the option you mentioned . Given the temperature the bulbs ( and special ceramic fitting ) reach -I'm not even sure the two can be used together - safety wise .
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