Programable Thermostat Hot Water Radiator Heat

Thank you for the response. I confirmed the current old thermostat is not operating on line voltage. Thus, I presume it's safe to hook up just about any of the thermostats that claim to operate on a variety of low voltage/millivolt systems. Unfortunately, I don't have the instructions for the system and the previous owner has passed away. The boiler is a 1976 Burnham with a Bell & Gossett pump, but that still doesn't necessarily give me the required thermostat voltgage. I also suspect the new thermostat does not "sense" the voltage of the system and must be properly set when installing. Guess I need to take the plunge and get a true voltage meter or order two thermostats in case I guess wrong and fry the first one!

Thanks again,

James