Have a Maple Chase thermostat -- undetermined age (probably 10 years or so). After electricity went out (and then back on) the heat did not kick back on. Checked batteries and fuse. All seem OK. When I set the fan to On it will just blow out cold air. (Have gas heat). Is there a reset button? This seems to happen a lot when changing from AC to heat in fall and spring but we somehow get it going again, but not this time!