Called Flash Codes. First try turning off everything at the breaker for at least 2 hours and preferably overnight. Turn back on and wait 15 minutes for self test to complete.
https://www.orionair.co.uk/PDF/fujitsu-trouble-shooting.pdf
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I have found that with my Fujitsu Halcyon, it needs to be disconnected from the mains at the breaker for 2 hours to properly reset. Use that time to clean the filters in the wall unit. The clicking you hear is self testing of relays.
I have the same unit. The drain line will be outside and is linked to the condensate drain on the outside refrigeration unit. It will be a black plastic or clear polythene tube a half inch in diameter. The bottom is probably blocked. A tech may be able to do it from the inside by blowing compressed Nitrogen gas down the drain. The case obviously has to come off which should be a quick job just 7 screws according to the video help.
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The error code 2F00 indicates a problem with the indoor unit's microcomputer. It could be caused by a malfunction in the microcomputer or the communication error between the indoor and outdoor units.
I think that is Clean Filter error. Lift up the flap and slide it out. Wash it and put it back. The other thing I found with mine is that turning it off at the breaker for 2 hours, fixes most issues.
Turn off the remote, hold down the temp raise button until you see the F or C appear, hit the temp raise button again to select F or C, turn on the remote.
