perhaps Doofy will save the day
From the sound of things there, I figured that he was promoted to upper management... :-(
the three other systems use one pump for one furnace, plus a backup..... the problem pumps are used for two furnaces, with 2 backups.......
Seems that they should split the paired furnaces and use the "one pump per furnace" system. (unless I misunderstood something).
Maybe something got into the hydrolics plumbing and clogging it?
