78 System frozen and not free in time - Defreezing Mode and Detection Errors (Back-flow line defreezing failed) - P20B9 Reagent - backflow tube heating Open circuit
System frozen and not free in time - Defreezing Mode and Detection Errors (Back-flow line defreezing failed) - P20B9 Reagent -backflow tube heating -open circuit
Hissing noise at expansion valve, Loss of refrigerant.Restriction in refrigerant system.Check receiver-dryer for uniformity of temperature.