The receiver-drier / Accumulator is strictly a disposable item and is thought of in the same terms as a fuel, oil, or air filter.

1. The receiver-drier / Accumulator must be changed each time a system is empty regardless of the reason for loss of refrigerant. Once the system is open to the atmosphere more than a short period of time, the desiccant can become “full” of moisture, which can lead to corrosion. This can cause the expansion valve or orifice tube to freeze, which can block refrigerant flow in the system.
2. It should also be changed every three years, because the desiccant pellets will break down and clog the expansion valve. This will in turn cause the system to become inoperable and May damage the compressor.
3. In fact, if any component fails or is replaced for any reason, the receiver-drier / Accumulator must also be replaced to prevent corrosion and moisture in the system.

In short, whenever you replace a component of the A/C system you must also replace the receiver-drier / Accumulator. If you do not change the receiver-drier / Accumulator there could be serious damage to the other parts of the system, which could be very costly. You must also have proof of changing the receiver-drier / Accumulator in order to receive a compressor warranty.