My thermostat works great during the summer but when the heat is on it will try to run all night even when desiref temp is reached. It did this last year and we had to completely reset then reboot. What a pain in my electric bill if we don't notice the running right away. Is there a default in the thermosta itself that we could change to prevent the running.

The thermostat is just basically a thermometer in the house which triggers the switch to turn the heat or air on and off as needed to maintain the selected temperature. The thermostat should be on all the time, but it should be cycling the heat or air conditioning on and off as needed to maintain that selected temperature that you have set.

It's a good idea to get your furnace cleaned and safey checked annually anyway, so I'd have a good HVAC contractor come out and do that, and ask them about this issue as well. A lot of people blow off this maintenance each year but it's a very bad idea to skip this service. If you have a gas furnace, it generates carbon monoxide and if the furnace is not working properly, it can release that deadly gas into your home and you would not even know because it has no smell and is invisible. With an annual service check, they can make sure the unit is not emitting carbon monoxide into your home, clean the unit and tune it up so it runs efficiently. While they are there, they can look into the issue of the unit staying on constantly all night.

If they then determine that the problem is that you need a new thermostat, that is not hard to switch out and you can probably do it yourself. You just follow the instructions on the package for installation. It's no more difficult than installing a light fixture, for example. If you buy a new one, get a good one - it's worth spending a bit more money to get one that can be programmed better because it will save you money over the long run.

I hope that helps.