View Full Version : Model s1-thec11p5s source one thermostat no heat

Feb 12, 2019, 12:55 AM
This thermostat has been working just fine for over a year. The cooling part is still working without problem, but the heating part will only supply heat occasionally. I changed the batteries and the filter. I put the mode button on heat, fan on auto, nothing happens. With mode on heat, and fan on, I get fan, no heat. The room temperature is 68, the desired heat temp. is set at 80. Why no heat?