Ll: S1+S2 Dialing Setting Error (For Ms04-12) - Midea VRF Series Service Manual

3.6 LL: S1+S2 dialing setting error (for MS04-12)

Digital display output
Description
 S1+S2 dialing setting error.
 All units stop running.
 Error code is displayed on the malfunction MS box.
 The indoor unit display board or wired controller connected to this MS displays "F8".
Trigger / recover condition
 Trigger condition: S1 and S2 are set to ON, but the indoor unit is connected to both pipes 1 and 2 (or the indoor unit is
connected to pipes 3 and 4).
 Recover condition: Does not meet trigger conditions.
 Reset method: Manually restart.
Possible causes
 S1+S2 dialing setting error.
 Signal cables are incorrectly connected.
 MS PCB damaged.
Procedure
S1+S2 dialing setting error.
Signal cable is incorrectly connected
Replace the MS main PCB
LL
No
No
Yes
Reset dial S1+S2.
Check and connect the signal cables
Yes
properly.
V6R VRF 50/60Hz
155