A/C Service Call: Description: - Last night I turned on the air conditioner...the tEcobee thermostat said it was 25 degrees in the house. The system ran for 4 hours and the temperature never came down at all. I shut the unit off at bedtime. This morning, the thermostat still said 25. I turned on the a.c. unit and the thermostat is dark...does not go on.