Early Coal Conversion Thermostatic Control???

sopcopotoptop

My family and I recently visited the Conrad-Caldwell house museum in Louisville, Kentucky’s historic district and I came across this curios device and plaque hanging in the back servants stair hall and was looking for any information I could come up with for it. Please read the plaque as the museum docents really are not sure about it either. There is wire coming from the backside of it but couldn’t tell it it really was connected to it. The boiler was originally coal fired but had been later converted or even completely replaced by gas fired I’m guessing. The house was built in 1893-1895. The Caldwells were very wealthy and had the latest when the hose was built including electric-combination lighting. So, any ideas about this curious device? Thank you.

Steamhead

It probably controlled a coal stoker or electric damper motor. Did you get a chance to see the boiler room?

sopcopotoptop

We took a guided tour but they also have a self guided tour as well. Will opt for that next year, if we go back, and beg a tour of the cellar. They say it’s cavernous!

HeatingHelp.com

This looks like a 1920's Powers Regulator Co., (Chicago, IL) Large Diaphragm Thermostat, as seen here: https://www.worthpoint.com/worthopedia/1920s-powers-regulator-co-large-1814541411

You can find more information about it's operation in this document (pg 31): https://archive.org/details/ShopAndOfficeTemperature/page/n31/mode/2up

Steamhead

@sopcopotoptop , you ought to pass this along next time you're there. And now I'd really love to see this system! Nice job, @HeatingHelp.com .