We had 3 mini splits installed in our home 5 years ago. After about 2 years, they started showing error code U0, repair person came, found a leak and fixed it.
Now, 2 years later, the 3 units keep shutting off every couple of hours and showing U0 code again. If we flip the breaker, they will work for a few hours then shut off again.
Another maintenance person came last week and said the pressure looked good and it's blowing cold so he didn't expect there was a leak. After a bunch of wandering around and not really taking anything apart, he concluded that there was reduced airflow because there was some dust inside the unit (not the filters that you can take out--those were clean). He said we would need to pay for a maintenance package if we wanted someone to come clean out the units to resolve the problem even though they are under warranty until 2030.
Any ideas what else it could be as I've read that this code could be caused by a faulty valve, compressor etc too.