radiant heat question

Hi, I recently bought a house that has radiant heat on the first floor, my problem is I was told buy the guy who owned the house before me that there is a sensor outside that kicks on the radiant heat whenever it is cold out. There is a dial in the boiler room that controls the radiant heat and when I turn it all the way off within a day or so it will turn itself back on again, the heating system is buderus.........Can anyone help? Thanks

Many boilers will fire if they sense the water may be getting close to freezing.

Normally, these things are controlled by a theromstat which often turns on the pump that circulates the water in the system. Hard to tell what's going on without more info.

do you have a model number ?
The device out side is called an outdoor reset and it controls the modulation of your boiler. Most of the settings are adjustable. I would go to www.buderus.net and downlaod the PDF manuals for your boiler and outdoor reset model number. My reset has the model number on the left side of the unit. The control may be mounted inside the boiler (on mine anyhow) so you may have to remove the cover

Lou