Indoor nor outdoor units were coming on when I arrived for service. Found control board at air handler had failed. Tested blower with direct line voltage before installing new board. Installed new board. Tested unit. First floor unit had a 14° split air handler. Checked pressures at condenser, found pressures were low. Recommend charging unit with R410A refrigerant as well as a UV dye to diagnose were leak is coming from. System operational.