Is Faulty Communication Wiring Causing Problems with Your Ductless Air Conditioner?

Ductless air conditioners (also known as mini-split air conditioners) are reliable and efficient climate control systems and are equally useful for keeping both residential and commercial buildings comfortably cool. However, these dependable air conditioners can still be vulnerable to malfunctions, and faulty communication wiring is a particularly common cause of ductless air conditioner failure.

Why is your ductless air conditioner's communication wiring so important?

All ductless air conditioning systems have a condenser, which cools the refrigerant used by the system's indoor vents to create cool air before transporting it to the individual vents. This condenser is always located outdoors, but your system's thermostat is located indoors. Consequently, the thermostat must be connected to the condenser by communication wiring, which usually runs through the walls and/or ceilings of your building. 

The thermostat uses this wiring to send instructions to the condenser, telling it to funnel more cold refrigerant towards the vents when indoor temperatures rise too high. When this wiring malfunctions, these signals can be distorted or cut off entirely, potentially causing the entire system to malfunction.

What causes communication wiring faults in ductless air conditioning systems?

In many cases, ductless AC systems malfunction because they were installed with the wrong type of communication wiring. Some air conditioning installation contractors use cheaper, 18 gauge communication wiring instead of the recommended 14/4 gauge wire, which can cause premature wire failure. 

Communication wiring faults can also be caused by physical damage, and wires are often accidentally cut during renovations. Environmental factors can also come into play, particularly in wires that run through the exterior walls of your property. Any moisture or condensation that reaches these wires can cause significant corrosion, especially if the wiring is not properly insulated with waterproof coatings.

Communication wiring that is located in the exterior walls of commercial buildings can be particularly vulnerable to corrosion since the walls of commercial buildings usually aren't as thoroughly insulated as those of residential homes. Specially-armored wiring should always be used in these walls, but this type of wiring is quite expensive and may be substituted for cheaper wire by unscrupulous contractors.

How can you tell if my ductless air conditioning system has faulty communication wiring?

Faulty communication wiring can cause a variety of problems in ductless air conditioning systems, including:

  • Error codes displayed on your thermostat or condenser status readout
  • Inconsistent air speed
  • System functioning in some modes but not others
  • The condenser activates but no air comes from the indoor vents

Unfortunately, these symptoms are far from distinctive and can be caused by a wide variety of other malfunctions. For this reason, you should always call in an air conditioning maintenance service if you suspect your ductless air conditioning system has faulty communication wiring. These services have the tools and experience needed to quickly find and fix the cause of your cooling woes.