3.Loosen the two thumbscrews on the bottom of the fan unit.
CAUTION: The fan unit weighs 16.8 kg (37 lb). Use extra caution when removing and replacing the top fan unit because it might be higher than your shoulders and is heavy and awkward to lift.
4.Pull the fan unit out toward you, and remove it from the MCS unit.
To replace this component, see "Replacing the fan unit (on page 52)."
Replacing the fan unit
1.Align the fan unit to the sliding rails.
CAUTION: The fan unit weighs 16.8 kg (37 lb). Use extra caution when removing and replacing the top fan unit because it might be higher than your shoulders and is heavy and awkward to lift.