My Soleus Air Conditioner model kfr-12gw/da keeps turning off with 4 blinks on the panel. I have had the R-22 added to specifications, yet it still turns off after 15 minutes. Had tech check system, coil is good, motor is good, no reason for it to be turning off and saying that the refrigerant is low. Can't check capacitor, and compressor is ok according to air cond. tech. Still do not know how to make it run longer than 15 minutes. Do you have any ideas???? Thanks