The freezer works but the fridge part doesn't want to cool....after being on for a while the air stops passing to the fridge and then there is some built up of ice in the wall of the freezer around some coils...and the fridge side warms up. Also, the digital temperature screen kind of blinks and there is a chipping sound that the fridge is making. We ordered the main board behind this temperature screen and replaced it, but the problem still exists. Don't know what to do next...please help!