It will say on your work order slip :thumb:.leobg said:Mine had this problem last summer. Had it in just before the 36K warranty expires. Humming noise was gone, now I think sometimes it does popping noise, but not always. I have extended warranty purchased, so hopefully if this develops into something worse, they will take care of it. I am not sure how they fixed it last fall, I mean not sure if I got new PS pump or they did something else.