I have an old oil furnace and I am looking for some clarification as to how it is supposed to work. It heats water filled radiators through out the house.
Currently it is connected to a thermostat by three wires. When it is needed the thermostat does heat the house but lets say it is 80 degrees outside, the radiators will not get hot but the furnace will still come on periodically for a short period of time. Is this how this system is supposed to run or might there be something wrong with the thermostat / wiring.
Note: The thermostat does manage the alert the furnace when it needs to but the air temperature is a bit different than the reading on the thermostat. ex thermostat says 65 and the actual temperature is 72.