I bought a Toshiba Firdge model GR-W40SI(W) running on 112Volt using step down transformer.The appliance has served me for years without troubling.Recently ther seems to be problem.The blowing air is not chilled and once the timer is off,it will not restart again.Please help me on the problem.No gas is leaking and all doors are well sealed and no air leakage.Domo sumimasen.