Iron Fireman Thermostat Question

CKNJ

I recently acquired an Iron Fireman Thermostat model T-114. Yeah, I collect things like this. But on this one, it is 2 wire (as you can see in photo). But it doesn't seem like the connection on the left connects to anything making me wonder how this worked? I also noticed the coil of wire around the bar and wondered if anyone knows what that was for?

Really appreciate any information on this unit. I have never seen one like it and nothing on the internet to help either. That was surprising because Iron Fireman was a big company at one time.

ratio

Without having it in my hand, I'd say that the frame, or some part of it, is connected to the terminal that doesn't connect to anything, and the coil of wire is going to be the anticipator, it connects in parallel with the contacts, right?

JUGHNE

Could you adjust the heat anticipator coil, (if that is what it is) by sliding the coil up and down on that bar. That would affect the movement of the long bi-metallic strip perhaps?

Jamie Hall

So simple. I love gadgets like that. And most likely both @ratio and @JUGHNE are right.

CKNJ

JUGHNE:. That wrap of wire is stationary. The ends are under the screws at each end. But I do believe it is an anticipator of some type.

I guess what I am trying to understand is how does it complete the circuit? I also haven't figured out what the 2 screws on the bottom right do.

To be honest, mostly I have seen the old Minneapolis Honeywell type so this really intrigued me. MH usually have a small wire that connects the arm to the ground terminal.

ratio

Maybe it's provisions for a function that this model doesn't have. Look at the arm towards the contacts. Does it have one, or a mark like one could go there, on the back side of it. Like for cooling maybe?

CKNJ

Just as a follow up for anyone interested. Yes, the thermostat grounds through the body. When heat is satisfied, the arm breaks contact with the adjustment screw on the left side (which is also adjustable for temperature swing) and then makes contact with the block where the two screws (lower right) are. Those 2 screws would have been connected to the Iron Fireman controls in the basement that would have kept the fire on stand by until the next call for heat.

Yeah, I am a geek.