Your thermostat is just a dumb switch.
OK, not as dumb as a light switch, because it knows if the temperature in the room has dropped below or risen above its set point, and it can turn itself on and off, and sure, some thermostats have schedules you can program in so they’ll turn on or off at a certain time, and most have a clumsy way of adapting themselves to the type of system you have so they don’t bounce on and off constantly, or overheat wildly, but really, your thermostat, even your sexy Nest, is really dumb. On or off. Those are your choices, and the on choice is ON, full throttle, heat me like it’s January First, 0 degrees Fahrenheit, and there’s a 40 mile an hour gale blowing. Your thermostat is to your heating system what a car with a gas pedal fixed at 60 miles per hour would be. Put the car in gear and away you scream at highway speed, even if you only need to go to the corner store for milk and bread.
About that Nest thermostat by the way; sure it can tell if you’re in the room, and it’s probably told the NSA all about it. Sure you can turn it up from your smart phone. The problem is, it knows nothing about your heating system, NOTHING, including what temperature it is outside. It doesn’t know the first thing about heat, and it doesn’t care. Nest has seduced you through your smart phone, and is codependent with your lazy ass as well. Why should you program your thermostat when the NSA can do it for you? The only efficiency the Nest gives you is that it keeps turning itself off. If you are too benighted to set a schedule on your programmable thermostat, I guess that counts as more efficient.
What’s the alternative? Something like Tekmar’s TN2 system, in which the thermostats are actually sensors, not switches, and the sensors can talk to one another and to the boiler so that the system knows what is going on at many points in the house as well as what the outside temperature is and can optimize the temperature of water the boiler will make, how long the boiler should run and where left over heat should be sent at the end of each heating cycle. Tekmar’s thermostats are the smart ones, and a system with them will also “learn”, but at a much deeper level than the Nest. TN2 thermostats have a touch screen; you can access them with a smartphone or computer, make changes in the system and get reports on what is going on. They were designed by heating engineers, to make heating systems work better. More heat geek than Candy Crush. Your choice.