Malfunctioning Mini-Splits: Is A Faulty Communication Wire To Blame?

Ductless mini-split air conditioners have two main components, which must work in tandem for the system to function correctly. The outdoor compressor unit vents waste heat and send chilled refrigerant to the indoor unit, which uses the refrigerant to cool the air inside your building.

To achieve this, your system's indoor and outdoor units are connected via communication wiring. These wires allow each unit to send electrical signals to the other, activating and deactivating components when necessary. If your mini-split system's communication wire is faulty or damaged, the system can suffer from serious malfunctions, and may not operate at all.

How Can You Tell If Your Mini-Split Has Communication Wire Problems?

The communication wire that connects your system's indoor unit to the outdoor unit is actually made up of several cables, which are bound together in a single sleeve. Each wire controls different functions of the system. Because of this, problems with the communication wire can cause a variety of problems, depending on which individual cable(s) are faulty.

In some cases, communication wire faults will prevent the indoor unit from activating when the outdoor unit activates, or vice versa. Faulty communication wire can also restrict the system's functionality; for example, if your system uses a two-stage or variable fan system, the indoor unit's fan may only work at certain speed settings.

Communication wire also transmits power between units, and damaged wiring may cause overvoltage problems. If your indoor unit smells like burning plastic when activated, deactivate the system immediately, as the communication wire may be sending too much power to the unit. This can seriously damage the system, and may pose a fire risk.

If your system is showing any of these symptoms, check the system's readout screen and/or warning lights. Systems with screens will display an error code that should tell you if a faulty communication wire is causing the problems. However, if your system's communication wire is seriously malfunctioning, or has been accidentally cut, your system may not power up at all, leaving the screen and/or lights blank.

What Should You Do If Your Mini-Split Has Communication Wire Problems?

If your mini-split air conditioner is suffering from any of these symptoms, you should call in a professional air conditioning repair service to find and fix the problem. Never attempt to fix a faulty communication wire yourself. Working with HVAC electrical systems can be very hazardous, and must be performed by a professional technician with dedicated HVAC electrical training.

If your service determines that faulty communication wiring is causing your problems, the wire will almost certainly need to be replaced. Split system communication wires are not hugely expensive and can be replaced relatively quickly by skilled technicians, so repair work usually won't break the bank.

However, replacing the wire can be more difficult if the original wiring was accidentally severed during remodeling work, or as a result of structural damage. In these cases, your service may need to create a new passage in your building's wall before the new communication wire can be fitted. Your service will work with you to make this process as fast and non-disruptive as possible. 

Contact a local AC repair company for more info. 

About Me

Perfecting My Home HVAC System

After dealing with almost constant air conditioner and furnace failures, I realized I might not be doing my part to keep my systems clean and operational. To sort out the issues, I turned to a professional repairman for help. He explained that since I wasn't changing the filters regularly, there was no telling what would happen. I learned how to clean evaporator coils, replace filters, and even sort out power failures on my own. I want other people to experience the confidence and comfort that comes along with protecting your own HVAC system, so I put up this blog.