Our house is heated by a Burnham boiler installed by the previous owner circa 1995. Even years I remove and vacuum the burner tubes and replace the thermocouple (after having one fail when less than 3 years old at one of the most inconvenient times possible).
This year I noticed some corrosion on the sheet metal shell of the boiler and big piles of rust beneath the burner tubes. I think the corrosion on the sheet metal is new; I am sure the big piles of rust are new. Photos follow.
Facing the boiler with the service panel removed. Left is to the left of this picture; right to the right.
Interior lower left.
Interior upper left corner.
Interior lower right.
Interior upper right.
Bottom, with most of the burner tubes removed, and the piles of rust are clearly visible.
So, what is going on? There has always been a little rust on the burners, but nothing like these piles below. The spots on the interior panels make me think that either exhaust is leaking, or steam is leaking. But, I only work on this one boiler, and am not a trained pro. I would be pleased to hear from folks who have seen similar, and can tell me what that turned out to be.