Samsung Air Conditioner Error Code E175

E175 indicates a mixed operation error in which more than two indoor units within the same Samsung multi-zone system are simultaneously requesting conflicting modes, some cooling and some heating at the same time. Because the system refrigerant circuit can only operate in one direction at a time, it cannot satisfy both demands and shuts down with this fault code. The error protects the system from attempting an impossible operating state that could damage compressor components.

A reset may temporarily clear E175 if the conflict was caused by a momentary glitch, but the error will return if the underlying cause is not resolved. If any indoor unit is still set to a different mode from the others after the reset, or if a faulty control board is sending the wrong signal, the fault will reappear. Address the root cause first before relying on a reset to clear the code.

If the fix is simply correcting the mode settings on the indoor unit controllers, there is no parts cost and a technician visit fee may be the only expense, typically in the range of $75 to $150 for a service call. If a faulty indoor unit control board is the cause, board replacement parts generally range from $80 to $250 depending on the unit model, plus labor. Communication wiring repairs fall somewhere in between depending on the extent of the damage.

Start by checking the operation mode set on every indoor unit in the system and confirm they are all set to the same mode, either all cooling or all heating. If the settings look consistent, power cycle all units and restart them in a unified mode. If the error returns, inspect the communication wiring between units and consider testing or replacing the control board of any indoor unit that appears to be sending a conflicting signal.

E175 itself is a protective fault rather than an immediate safety hazard. The system stops operation to prevent the compressor and refrigerant circuit from being forced into a conflicting state that could cause mechanical damage over time. Continued attempts to run the system while ignoring this error could lead to compressor stress or premature component failure, so the issue should be resolved before resuming normal operation.