Ductless mini-splits are the workhorses of Hawaii cooling, and they are reliable, but island conditions produce a handful of repeat problems. Here are the ones we see weekly in Honolulu, Kihei and Kona.
The blinking light
Every brand uses a blink pattern or on-screen code. The most common in Hawaii point to a communication fault between indoor and outdoor units (often corroded wiring), a sensor failure or a refrigerant problem. Try a full power reset at the breaker for two minutes. If it returns, note the pattern and call for mini-split repair; knowing the code saves diagnostic time.
Water dripping from the indoor head
Almost always a clogged condensate drain. Algae grows in the drain line in humid weather and backs water up into the head. If the head has a condensate pump, a failed pump does the same. Turn the unit off to protect your wall and floor. A drain flush and treatment is a quick repair.
The musty smell
Mold on the blower wheel and coil. It is harmless to the unit but not to your lungs. A deep clean (removing the wheel, cleaning the coil, sanitizing the drain pan) eliminates it. Running the unit in fan mode for 20 minutes before shutdown dries the coil and slows regrowth; some units have a built-in dry function.
Cooling but not enough
Dirty filters, a coated coil or a slow refrigerant leak at the flare fittings. Flare leaks are common on installs where the fittings were not torqued correctly; our leak repair re-flares and tests them.
Outdoor unit never starts
Check the disconnect, then the breaker. If both are fine, it is usually the inverter board, a start component or a communication wire. Inverter boards are brand specific, so call a company that stocks them.
Mini-split pages for Honolulu, Mililani, Kihei, Kailua-Kona and Kapaa.