Is there a transferable warranty, the Sludge story is what my BSn
installer told me and is used by some to get replacement sales or could
be his way for an out. Steam lines wont sludge up but the bottom of the
boiler can. Is there air in the system, did you blead radiators, what is
the water temp and altitude. You probably need a different pro to go
over the whole system, it could be anything even an improper install.
Call the manufacturer of the system.