What's this thing here on the boiler?

[steamydream]

Hello, picked up an unloved mini 2, trying to resolve some issues. I can't help but notice that something that should have wires connected to it - doesn't
So underneath the earth wire (yellow/green) what is this thing and why no wires on it?
thanks

IMG_3981.JPG (171.32 KiB) Viewed 6099 times

[MDL]

I beleive that is the thermal switch to shut things down if the temperature gets too high. It also looks as if your fill sensor is not connected (the connection/thing in the center.

[steamydream]

Update, yes you are right, I've noticed the previous owner has fitted some sort of aftermarket pressure valve? Bizzare.

[chas]

A lot of people have posted photos of their S1's on this Forum over the years. I think we can safely say yours gets the award for ugliest steam boiler!

It is interesting that you are not getting overflow issues (assuming you aren't) since there seems to be no wire connected to the water level sensor.

A far as your disconnected thermal sensor, normally the steam boiler power lead goes to one side of this device and a short jumper connects the other side to the heater element lead. That way the power is shut off in case the temperature of the boiler get too high.

s1v2/images/SIBoilerTop.jpg

As you can see in comparing this photo to your device, so long as they use the correct gauge of wire there is absolutely no factory standardization on the wire color used.