Thanks for the picture! And the explanation! I wouldn't have thought of this.

After looking it up, I'm sure this must be a thermopile system. That or mercury vapor maybe?

I shut it off last night to cool down, but by time I remembered to check if it was cool enough to install the logs and start looking closely, it was bedtime. I won't have time today or tonight, busy day ahead, but I will report back when I do!

I'll dust it first to be sure, but I think you're right, it might need turned down a tiny bit. Thank you!