I have the same problem... what did you figure out? Mine is flashing 1C as well (which i think means freezing danger (but that makes no sense because the temperature is 39 celcius. THe pump has been running for 10 hours... even though i have it set for a 2hr cycle
Also.... Dpes anyone know how to change the top control to farenheit???
Call 1-616-871-3400 and speak to someone at great lakes. They should be able to walk you through it. or you can go to balboacontrols.com and search for your control pack