I grew up in a home heated with an Anthracite hand fired boiler. It provide central heat plus hot water. In summer a much smaller, 24-30 inch tall cast iron boiler was used to heat domestic hot water. My parents called it a "Jack Stove". Does anyone know of this term? Is it a generic name or perhaps a brand name? It really wasn't a stove but a small boiler with 1 inch supply and return fittings. The supply came out the top in a vertical pipe that had a clamped on gadget that regulated the fire box draft. Best I remember it was a 6-8 inch flat cylinder that was heated by the pipe. It had a chain that went to the hinged firebox door. As the pipe got hot the door opened increasing the draft over the firebox. Completly passive system. Wish I had it today.
I guess I should have said flat disk. It was about 8 inches in diameter and maybe two inches thick. I suspect it had two pieces of bi-metalic metal in it. As it warmed up from the pipe it was clamped to it deflected a long lever arm that projected from one disk. The lever arm moved up and via a chain opened the firebox door. I'll post my question on another Anthracite forum and see if I get an answer there.
Yes, that's the design. The one my parents had was very similar. Note the tab on the hinged firebox door. That's where the draft regulator chain was hooked. The shaker grates were operated the same way, with a front removable crank handle. The ebay listing gave me some hints for finding these units. I'm 40-50 miles south of PA Amish area. Wonder what they use today?