Service Manual SM-MDS_(ii) 75
Indoor pump error
Error Code: Decorative Error code #3, FB (For MC301)
Check the indoor pump.
Is it functioning normally?
Check the drain hose and pump
for blockage. Clean it and restart
the system
Replace the water level switch
Check the water level switch.
Is it functioning normally?
Is the indoor unit installed
properly?
Align the indoor unit properly
and restart the system