Contact Us

Send Message

Subscribe to our RSS Feed Articles & Tips

Ductless A/C Troubleshooting Tips to Avoid Emergency Repairs

What should you do if the ductless A/C system in your Chicago area home is not performing like it should? Before you call for emergency repairs, you may be able to diagnose, or even fix the problem with this ductless A/C troubleshooting guide.  

How Does Your Ductless A/C System Work?

Before you begin your ductless A/C troubleshooting, it's important to understand just how this type of system works. There are two major components. One is the outdoor compressor/condenser and the other one is a small indoor air handler that delivers the conditioned air directly to the room where it is installed. The air handler is connected with a conduit that contains power, refrigerant and other lines. 

When you turn the cooling cycle on, the refrigerant and the compressor create cool air, which is then pumped to the indoor unit, where the air handler distributes it. The wall mounted interior unit also sucks the hot air out of the room, and the condensation from within the handler, and pumps them both outdoors.

Ductless A/C Troubleshooting Tips

1. The unit won't turn on

  • If you have recently turned off the A/C, or there has been an interruption in power, you may need to wait between three to five minutes before turning it back on, thanks to a built-in safety feature designed to prevent the fuses from blowing.
  • Check the power supply to the outdoor unit. If the breaker is tripped, visually inspect the electrical connections to make sure they're tight and undamaged. If you reset the breaker and restart the unit, to have it trip again, leave the system off and call for service.
  • Gauge the temperature of the room and the setpoint for the A/C, making sure the setpoint is several degrees lower, and that the unit is set to cooling mode.
  • If you're attempting to turn the A/C on with the remote, check the batteries.
  • If the remote is broken or lost, there may be an emergency on/off switch on the fan coil unit that will do the trick. Without the remote it will only cool the room to the default temperature, though.
  • Check the display unit on the fan coil: if there is an E for error, followed by a number, you may be able to diagnose the problem by referring to the owner's manual.

2. You're hearing strange noises

  • Some sounds are associated with the normal operation of your ductless A/C, such as a squeaking noise while the unit is running, which may be caused by the effect of temperature fluctuations on unit's cover.
  • When the system is in heating mode, you may hear a periodic crackling sound as various components begin to defrost.

3. The fan is blowing but it's not cooling the room.

  • Ductless A/C troubleshooting for this symptom should begin with the air filter. Regular maintenance should include washing reusable filters every four to six weeks, or changing out clogged replaceable filters.
  • Inspect the outside coil for an accumulation of ice. Check if the fan is operating and the blower wheel can move. If the wheel is moving but the fan isn't working, it may be the control board or the motor. If the fan is working, the refrigerant level might be too low, which will require service.
  • Ensure there are no blockages of the intake grille or outlet port.

4. Water is leaking from the outdoor unit

  • Continue your ductless A/C troubleshooting by inspecting the drain hose for blockages.
  • If the hose is clear, check the unit for the correct positioning. The fan coil unit should have a slight slope to allow for drainage.

For more help with ductless A/C troubleshooting, or any other HVAC concerns, call the experts at, proudly serving homeowners in SW Michigan, NW Indiana and Chicagoland.

Written by

Back to Articles