Ductless mini-splits are good at telling you something is wrong. A blinking light on the indoor unit, or a code on the remote or wall controller, is the system reporting a fault it has detected. The code itself is the most useful thing you can give a technician.
First: write it down
- Which light is blinking (operation, timer, or another), and its color.
- How many times it blinks before it pauses. Count a few rounds.
- Any letters and numbers on the remote or wall controller. On many Mitsubishi Electric systems, a code can be read from the remote; your owner's manual explains how.
What you can safely try
- Check the filters in the indoor unit. Dirty filters cause many faults. See how to clean them.
- Check the outdoor unit for leaves, debris or anything blocking its fan.
- Power it off and on. Turn the system off at its breaker or disconnect, wait a few minutes, and turn it back on. If the code was a passing glitch, it clears. If it comes back, it's real.
Common causes
- Drain problems. A clogged condensate line or pump can stop the unit to prevent a leak.
- Sensor faults. A temperature sensor on the coil or in the room has failed or come loose.
- Communication errors between the indoor and outdoor units, often from a wiring connection.
- Refrigerant problems. A leak shows up as poor heating or cooling and, eventually, a fault.
When to call
If the code comes back after a restart, or the unit won't heat or cool, call us at 805-965-6326 or send us a message with the code. We're a Mitsubishi Electric Diamond Contractor, and we install and service ductless systems.
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