bar joist identification

huangyhg

bar joist identification
i am trying to determine the capacity of existing roof joists for new hvac units.
i found the identification tags, which read "06-8656 nj 12" "20-b7".
here are measurements that i took:
  the joist depth is 20 inches.
  bearing depth is 2 1/2 inches.
  top & bottom chords are cold-formed steel and parallel.
  web membs are 3/4" in diameter.
  there are two rows of horizontal bridging.
  the building was built after 1963.
i could not come up with any spec or load carrying capacities by looking up the sji's "75 year steel joist manual".
thank you for any help to determine joist spec or capacity.
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