Checked Combi Oven unit, found probes coated. cleaned. ran unit found similar issue. checked errors found errors 1,3,2, found issue in full valve will need to order and return. customer also wants a case of descaler (part order). 1/11/19 Replaced valve and ran unit. found unit had error 4 and would not heat upon checking found error 4 is a fair probe fault. checked over found probe wire broke off probe behind cover. removed probe took apart and got it to work temporarily until probe comes in. will order and return. 1-17-19 Removed left side panel to access probe. Removed failed probe, installed new probe, energized and checked operation. Unit operating normally at this time. ** No Travel Charge per Service Manager**