First off, you can plug 15A power cords into 20A circuits. If you try to draw more than 15A, which you can from a 20A circuit, with a 15A cord, you will have a problem. If you draw less than 15A, you're OK. Most newer houses run 20A circuits (12AWG) for electrical outlets. Building codes let builders use 15A outlets unless it's the only outlet on the circuit. Builders use the 15A outlets because they are cheaper.
Before you replace an outlet, you need to turn off the circuit breaker to that outlet. If it's a 20A breaker, you can use a 20A outlet. Also, the wire should be 12 AWG. If it's a 15A breaker(usually used for overhead lighting), you can only use a 15A outlet. The wire then would be only 14AWG.
Before you replace an outlet, you need to turn off the circuit breaker to that outlet. If it's a 20A breaker, you can use a 20A outlet. Also, the wire should be 12 AWG. If it's a 15A breaker(usually used for overhead lighting), you can only use a 15A outlet. The wire then would be only 14AWG.