Ductless air conditioning units are an alternative to central forced air systems, which consist of individual units that are installed in each room of your home. This allows a degree of climate control customization that is not possible with central forced air systems, which can translate into lower energy bills each month. However, like all other appliances and climate control systems, individual ductless air conditioner units can begin to break down and malfunction, causing your units to produce less cooling and use increased energy consumption.
One of the primary reasons why your ductless air conditioner is no longer functioning properly is because of some sort of damage or needed maintenance to the unit's power source. The most common variant of this problem is dead or dying batteries within the remote control for your unit, which means that your unit may not be turning on when you want it to. Beyond this, you should also take a look at your unit's power source and wiring to see if there is any damage to the unit itself which may be affecting the performance of your air conditioning unit.
Check the Filter
Just like all other types of air conditioners, your ductless unit makes use of an air filter to remove dust and other airborne particles from the air supply below it blows chilled air throughout your room. Air filters will necessarily become clogged over time with regular usage, and will need to be replaced. You can usually just slide air filters out of their casings within the unit by hand (though in some cases you may need a screwdriver or wrench to remove a fastener) and replace them with a new one.
Interior Vent Clogs
In rare cases, if your air filter has been completely or overly clogged for an extended period of time and dust and other debris has managed to make it into the interior of your unit, the output vents of your air conditioner can become clogged and completely blocked as well. You can determine this by opening the hood over your ductless air conditioning unit and inspecting it up close with a flashlight: look for signs of built up dirt, dust, staining, discoloration and other signs of debris and clogs. If the vents within the interior of your unit are blocked, you need to get in contact with a home ac repair professional to clean them out for you using specialized tools.