LAARS FTHW, FTHF "CASCADING" Circuit Board Revisions (SFN)
It is IMPERATIVE that all boilers circuit boards in the cascade have the SAME EXACT revision(SFN) . Meaning you can NOT mix revisions (SFN's) in a cascade.
In example, you can NOT properly cascade a revision 10 (SFN) with a revision 1.01 (SFN).
ALL REVISIONS (SFN's) MUST BE THE SAME in a cascade regardless of how many boilers are cascaded.
Furthermore for example, if down the road, a circuit board must be replaced , we MUST assure that the remaining circuit boards in the cascade ALSO have the same revision (SFN) as the recently replaced circuit board.