Arrived on site to diagnose a 4 year old unit. Spoke to client and he stated thermostat just had went blank. Client has been doing some work around house and just noticed unit is blank. Thermostat was a white I comfort and checked and no power. Inspected indoor unit and found unit to not have any power. Found no 120 was going to system. Checked breaker and it was tripped. Flipped back over and in it was operational. Cycled unit and was operational. Did it a couple times and was good. Advised client of findings and board and thermostat were good and operational. Advised client no protection on unit and recommended adding protection to help prevent and protect systems from electrical surges and power that can damage or even short out systems and components. Client is aware and stated he wanted to talk to wife and stated to follow up tomorrow as to what he would want to do. He would let me know then what he would like to do. Cycled unit and unit is operational Upon departure.