Came out today for a heat pump not operating properly. I called for heat and noticed that the suction line is ice cold. I went to the condenser and saw an error code 429-inverter has detected a dc link low voltage condition. If this occurs 10 times during a one hour period, the outdoor unit is locked out. I then cut all power to the system to try and reset the system. I turned the system back on and got the same results. I then reached out to PA and he gave me some other trouble shooting ideas. I went through trouble shooting with PA with no success. I then tried to run the AC to get a superheat and subcool reading but the system would not run. PA will return to do further diagnosis.