Thermostat question

[Orrex]

If you set the thermostat at 68°, does the furnace kick on when it dips to 67.9° and then switch off again when it reaches 68°, or is there some "grace period?"

Or does it actually heat to, say, 70° to allow for some wiggle room? Wouldn't the furnace run 24/7 otherwise?

[MineralMan]

1. There's a temperature spread

in which it operates. Usually a couple of degrees. It depends on the thermostat model. Once your house is warmed to the target temperature, it will hold that heat for some time. when it drops a degree or two, depending on the thermostat model, the furnace will kick in.

[NewJeffCT]

2. There is usually a 1 to 2 degree tolerance built into the thermostat

and, I'm pretty sure it doesn't heat up to 70. We keep ours set around 68 in the winter and it will stick to 68 degrees most of the time, and I can hear the furnace kick on once in a while - I'm guessing it happens when the temp threatens to drop to 67.

I'm guessing it heats up to 68.49 or so, and then when the temp drops to 67.50, it kicks on again, warming the house up to 68.49 or so and then turning off. If your home/apt/condo is well insulated, it will hopefully take a while to drop down to where the furnace kicks on again.