Compatible parts can offer a lower-cost alternative for components like capacitors, fan blades, or door seals, where manufacturing tolerances are less critical to overall system performance, though quality varies considerably between suppliers. For more sensitive components, such as compressors, PCBs, or refrigerant-specific expansion valves, mismatched specifications in a compatible part can lead to inefficient operation or even accelerated failure of surrounding components, since the whole system is engineered around a specific part's exact behavior.