Blows cold (refrigerated ) air when set for 80 degrees and outside temp is below 70 degrees. When set for "HI" temp, the heat does come on. Is the climate control thermostat unit failing or is there something else I can check? Also, does the unit detect daylight versus night? Sometimes it works ok when starting from inside garage then next time started after setting outside in sunlight, I get the previous problem of cold air.