A basic Honeywell control can control heat and air conditioning. This one is a basic thermostat. There are two kinds of thermostats, programmable and the regular kind. The regular one has to be adjusted yourself. The programmable one can be programmed to turn down the heat when your bedtime comes and turn up the heat when you are ready to get up, or when you go away, like on a vacation or work when heat is not needed as much.
Honeywell heating controls control the furnace in your home. This is mainly gas or oil furnaces that heating controls mostly control. I don’t know if this works for water, or boiler heating, as the boiler heating is different than these other kinds. I think the boiler heater would have another type of control for it. Yes, I believe it does.
A boiler control is different as it is a larger panel. A boiler can heat bigger buildings than a regular house, normally. Like, in our apartment, a boiler heats this rather than us having our own thermostats. Boilers heat water with gas to keep the building warm. If you have to replace a boiler, then you would be advised to replace the boiler control so that it will be compatible with the new boiler.
Sometimes with the older mercury thermostats, they may not be level because the wall was painted at a later time and the thermostat was not put back onto the wall levelly. These needs to be level to work right because of the little drops of mercury are in a glass tube and this mercury drop is finicky! This is why, if you have this old style Honeywell heat controller, then you need to make sure it is level, if you are having problems.
Programmable Honeywell heat controls are the best thing to have because you can save energy. When you have this you can program it to drop heat level when you go to bed and by morning when you get out of bed it can be programmed to turn up the heat for you. This is great, so you don’t have to be in a chilly house after you had gotten out from under the covers. And it is good too, because you can program it to cut back on the heat when you leave for work, and soon before work, it can be programmed to turn up the heat for you so you can have a warm house when you get home.
I think the thermostats have changed greatly over the years. We have an old thermostat in the room and it is out of use as we have a boiler. What is in the thermostat is a “blob” of mercury that would conduct more electricity to the controller if we had wanted more heat. Now, because of the mercury concerns, I don’t think they make this kind anymore. The newest ones are electronic, and others may have a spring like mechanism. I think the mercury based ones have been discontinued for quite some time now.