The symptom your describing certainly sounds like this is a fill overfill circuit problem. The fact that you can only drain the unit and nothing more points directly to a fill overfill problem.
If the overflow switch is activated that is exactly what the unit will do. The overflow switch is item 11 this link:
(PART NUMBER: 8268909)
Additionally if the float is stuck in the UP positon from food particulate build up on the stem it will not fill with water ever. The float assembly is item 13 of the above link. You can clean up the float assembly and the float switch most of the time and get the unit to perform normally. Occasonally parts are required but on a 2 year old unit I seriously doubt either part has failed. Just clean them up and test again. I think this will resolve the problem.
I just have issues with Sears in home service not even considering either float assembly or the overlow switch as the most probable cause of your symptom. In all seriousness if Sears was the reason for having a control panel change you have the right to ask that the part be removed and your original control panel re-installed. Your money and labor expended installing the control panel should be refunded refunded.
You really need to get in touch with the Sears Service manager and tell that person you want a competent technician that will correct the problem. I.e. do not send the previous tech out for any reason other than to reinstall the old control panel. After that... send someone else but fix it. Had you called me and I had one of my techs change a control panel that did not fix the problem the tech would be working that job for free..... The only thing you would be charged for on a call back would be labor to install any additional parts and the cost of that part. NO SERVICE CALL charges on a call back. (Just my 2 cents)
Check the float switch POWER REMOVED... by gently raising and lowering the float. You should hear a click near the top of the float travel and again as the float lowers. The over-flow switch works in the same manner. Clean up the stem on item 13.... below link and it should work.
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