Posted by Ted on January 04, 2000 at 08:48:28:
I have been experiencing a muffled "thud" in my pipes once the house comes up to temperature. I have a two pipe steam system. The "thud" resonates throughout the house as the the system begins to cool and is noticably louder in the evenings. Can this be caused by the expansion and contraction of the pipes and radiators or is this a symptom of other problems. It definitely occurs after the boiler has shut down for at leat one half hour. As always, all advice is welcome.