please help me , i have the same problem too
i currently doing my Final Year Project and i facing this problem , i doing a PIC16F876A to control the desk fan using relay and LCD display , which when i switch on auto mode , the certain relay will switch on according to surrounding temperature , when i not connected my relay circuit to 240 AC desk fan , its work perfectly , i can switch to auto and manual , but once i connected to 240AC desk fan , when i switch to auto mode , i cant control it anymore , and my LCD screen appear many weird wording . i think its AC motor generate noise and disturb get my relay and pic circuit , i had done many thing like put a capacitor at all my circuit , i had put a 0.1uF cap at the AC motor supply , but it still cant work , got any method to overcome this problem?please help me , thanks alot