I always have the fan inside on because it is connected to a hepa filter system. Recently, the central ac I shut off at the thermostat and it showed that it was off. However, the compressor continued running outside and I was unaware. Hours later when I return the thermostat said the room temp was 70 (it was set at 76 for ac). The house was freezing and it was 77 outside. I shut down the system by the circuit breaker. Later I took the thermostat off and looked at it,( I accidentally had nudged it the other day before). I disconnected and reconnected the 3 wires y,g, and r... I turned the circuit breaker back on and the compressor was off (I did try turning the circuit breaker on before I took the thermostat off and the compressor was still running). I then turned the ac on and the compressor went on, then I shut off the ac (still cold in house and outside was now cold) and the ac compressor went off . I noticed that the y (white) wire and g (green) wire were slighty over each other . Could it be possible the bear parts of the wire were touching each other and this caused the problem. Because I separated them when I placed them back on . I haven't used ac since cause I don't want the compressor running constantly... Could these 2 wires have cause this? The ac is a Carrier and is only 6 yrs old and the thermostat is a non programmable Honeywell that is only 6 yrs old.