Trane GAM5B0A18M11EB Installation, Operation And Maintenance Manual page 9

STEP 6 - Use a 5/16 Allen wrench on the locking
mechanism on each side of the bottom half of the
cabinet to loosen the locking mechanism. The locks
loosen by turning counter-clockwise approximately
3/4 of a turn.
STEP 7 - Lift the Coil section up and away from the
Blower section. Set aside.
Note: When separating the two cabinet pieces,
make sure the gasket remains intact.
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