New sump pump issues

We had a new sump pump put in yesterday as our old one failed. It's not the typical vertical or float switch but a pressure/diaphragm switch (has the plastic tube coming out of the plug). Our pump runs at least 4-6 times per minute during wet times, and is doing so now. Problem is we noticed the pump getting louder as it sucked the water up and out, but in the morning our backup had kicked in and our main wasn't running. I unplugged and plugged it back in and it fired up. I've done this 3 times already today. What's going on? I'm assuming it's overheating, but our last pump never did this in the three years we had lived here. Ideas?