The key indicator of cardiac illness is the electrocardiogram. Lacking of cardiac experts is creating a challenging issue in developing country, especially in Covid situation. Therefore, an expert system required to solve this problem. The presented detector solves this problem by the identification of various peaks of ECG using wavelet transform. Wavelet clearly indicates the frequency and time information of the signal. There are two separate results are presented in the paper about QRS complex and the P, T waves. For QRS complex detection Sym-8 with rigrsure (threshold) gives 99.35% sensitivity. In P and T waves Sym-8 shows 99.65% sensitivity. The comparative analysis of different wavelets also presented. For the purpose of testing the study, the signals from the MIT-BIH's arrhythmia database were employed.