Just put in a new Dunkirk boiler last fall, everything ran good all winter long. Around April of this year, I began to hear a vibration noise coming from the cir. pump. The noise kept getting louder and louder, now I can hear it all through my baseboard pipes when the boiler turns on. This is the first boiler I had with a Taco pump on it, always had Grundfos. Don't know much about these Tacos, do they have some kind of bearing in them that could be going bad. I can't seem to find out why the pump is making a vibration noise like that. Can anyone help me out?