From my checking the relay on the circuit board is bad. Some time the unit kick on some time it don't, it does good at night but in the day time that relay on that board sticks. The unit is just two years ild and the board is bad already. Sorry I have not been around but the last past six weeks they have been running me crazy with this little heat wave in New Orleans,Louisiana. You all know these people down here can not take no heat.