My thermostat has always worked just fine, however in the past few days I have noticed that it felt chilly so I check the temp and its lower than my setting (i.e. set for 68, current temp 66). In order for the heat to turn on, I have to turn the thermostat off and so far that corrects the problem, triggering the furnace. However, it is now happening more frequently so it's becoming a problem.

Suggestions? I'm thinking I either need a new thermostat or perhaps a check to the wiring.

On a sidenote, I would like for the thermostat face to be flush with the wall, is it okay for the thermostat to be inset into the wall or with this interfere with the functions?

Thanks in advance and if you answers could be in layman (or better yet, laywomen : ) terms, that would be great.