In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Noisy pipes near boiler when only 1 zone is open
Hello, 2 years ago I had a triangle tube solo 175 boiler installed and it uses a grundfos 3 speed circulator pump (ups26-99fc). It replaced an old leaky boiler from the 60,s. The existing piping was used, there are 4 zones using white Rodgers zone valves. System has worked very well until this heating season. When the boiler is running with only one zone open it makes a loud "crackling" sound which seems to be the loudest about 3 feet after the pump before the zone valves. If two or more zones are open the sound is non-existant. What things should I check? Could it be the pump? I am thinking something else since it is quiet when more zones are open. I don't think the system has any inhibitor in it, would this help quiet it down when only one zone runs? Thanks in advance for any advice!