Si12-308 Control SpecificationFunction and Control 1073.15 Wiring-Error CheckOutline The convenient Wiring Error Check function is designed for the microcomputer to correct wiringerrors itself.If local wiring is unclear in the case of buried piping, for example, just press the wiring errorcheck switch that is behind the right-hand panel of the outdoor unit. Even if the connections forRoom A and Room B are confused, the system may run without a hassle. Note that this checkfunction does not work in the following cases. For about 30 seconds after the power is turned on (during initial setup). For 3-minute standby period after the compressor has stopped. When the outdoor air temperature is below 5°C. If the indoor unit is in trouble (also in case of all-room transmission failure).When the piping and wiring are perfect, there is no need to use this function.Operation 1. Remove the 5 screws from the service panel (right side panel) and detach the panel.2. Press the wiring error check switch on the service monitor PCB, and the wiring error checkfunction is activated.3. In about 10-15 minutes, the checking will end automatically.4. When the checking is over, the service monitor LED indicators start flashing.Self-correction complete…The LED indicators 1 ~ 4 flash one after another.Self-correction impossible…The LED indicators flash all at the same time. Transmission failure occurs at any of the indoor units. The indoor unit heat exchanger thermistor is disconnected. An indoor unit is in trouble (if a trouble occurs during the wiring error checking).Emergency stop…Any of the LED indicators 1 ~ 4 stays on.Note: 1. It takes about 10-15 minutes (after pressing the wiring error check switch) to complete thechecking. (Wrong wiring between the upper and lower units cannot be self-corrected.)2. Wrongly connected liquid and gas pipes cannot be self-corrected either. Be sure to make theliquid pipe and the gas pipe in pairs.3. To forced-terminate the wiring error check procedure halfway, press the wiring error checkswitch again.In this case, the microcomputer's memory gets back to its initial status (Room A wiring →Port A piping, Room B wiring → Port B piping).4. In replacing the outdoor unit PCB, be sure to use this function.5. Make the power slide setting after doing the wiring error checking. (Otherwise, if the wiring isreversed, the air-conditioners being connected are set up in the reverse way.)Basic Knowledge This function works in this way. Refrigerant is let flow from Port A and on. The temperaturesof the indoor unit heat exchanger thermistors are detected one by one to check up thematching between the pipes and wiring. With this function on, freezing (crackling) noise may be heard from the indoor unit. This isnot a problem. (This is because the heat exchange temperature is made to drop below 0°Cin order to increase the detection accuracy.) The indoor fan is made to turn on and off at the same time.LED 1 2 3 4 JudgmentStatus All flashing at once Self-correction impossibleFlashing one after another Self-correction complete