What does ACH US TREASury xxciv ser mean?

A direct deposit "ACH" with a tag "US TREASURY 312 XXCIV SERV" means from the US Treasury San Francisco Processing Center (312); with garnishment rules (XX) (as oppose to prior to garishment rules without XX); Civil Service Retirement. See reference US Gov 'Greenbook'

note: Treasury/FMS to be positioned for future use of the "XX" identifier for other payments,

should additional authority be acquired. If "XX" there is no garnish.